{ "version": 1, "generatedFrom": "src/data/units.js", "categories": { "length": { "name": "Length", "base": "m", "dimension": "length", "description": "Distance and length measurements from atomic and manufacturing scales through surveying and astronomy.", "units": [ { "id": "nm", "name": "Nanometer", "symbol": "nm", "aliases": [ "nanometer", "nanometers", "nanometre", "nanometres" ], "description": "One billionth of a meter.", "system": "SI", "definition": "1 nm = 10⁻⁹ m", "usage": "Microscopic dimensions", "transform": "linear", "factor": 1e-9 }, { "id": "um", "name": "Micrometer", "symbol": "µm", "aliases": [ "um", "μm", "micrometer", "micrometers", "micrometre", "micrometres", "micron", "microns" ], "description": "One millionth of a meter.", "system": "SI", "definition": "1 µm = 10⁻⁶ m", "usage": "Small-scale measurements", "transform": "linear", "factor": 0.000001 }, { "id": "pm", "name": "Picometer", "symbol": "pm", "aliases": [ "picometer", "picometers", "picometre", "picometres" ], "description": "One trillionth of a meter.", "system": "SI", "definition": "1 pm = 10⁻¹² m", "usage": "Atomic and molecular dimensions", "transform": "linear", "factor": 1e-12 }, { "id": "angstrom", "name": "Ångström", "symbol": "Å", "aliases": [ "angstrom", "angstroms", "ångström", "ångströms" ], "description": "One ten-billionth of a meter.", "system": "Scientific", "definition": "1 Å = 10⁻¹⁰ m", "usage": "Atomic scales", "transform": "linear", "factor": 1e-10 }, { "id": "mil", "name": "Mil", "symbol": "mil", "aliases": [ "thou", "thousandth inch" ], "description": "One thousandth of an inch.", "system": "US", "definition": "1 mil = 0.001 in = 0.0000254 m", "usage": "Manufacturing", "transform": "linear", "factor": 0.0000254 }, { "id": "mm", "name": "Millimeter", "symbol": "mm", "aliases": [ "millimeter", "millimeters", "millimetre", "millimetres" ], "description": "One thousandth of a meter.", "system": "SI", "definition": "1 mm = 0.001 m", "usage": "Everyday small measurements", "transform": "linear", "factor": 0.001 }, { "id": "cm", "name": "Centimeter", "symbol": "cm", "aliases": [ "centimeter", "centimeters", "centimetre", "centimetres" ], "description": "One hundredth of a meter.", "system": "SI", "definition": "1 cm = 0.01 m", "usage": "Body and object dimensions", "transform": "linear", "factor": 0.01 }, { "id": "in", "name": "Inch", "symbol": "in", "aliases": [ "inch", "inches", "\"" ], "description": "International inch.", "system": "International/US", "definition": "1 in = exactly 0.0254 m", "usage": "Small dimensions", "transform": "linear", "factor": 0.0254 }, { "id": "hand", "name": "Hand", "symbol": "hand", "aliases": [ "hands" ], "description": "Equine height measure equal to four international inches.", "system": "Imperial/Equestrian", "definition": "1 hand = exactly 4 in = 0.1016 m", "usage": "Horse height", "transform": "linear", "factor": 0.1016 }, { "id": "link", "name": "Link", "symbol": "li", "aliases": [ "survey link", "links" ], "description": "One hundredth of an international survey chain.", "system": "Survey", "definition": "1 link = 0.201168 m", "usage": "Land surveying", "transform": "linear", "factor": 0.201168 }, { "id": "ft", "name": "Foot", "symbol": "ft", "aliases": [ "foot", "feet", "'", "foot international" ], "description": "International foot.", "system": "International/US", "definition": "1 ft = exactly 0.3048 m", "usage": "Height and construction", "transform": "linear", "factor": 0.3048 }, { "id": "yd", "name": "Yard", "symbol": "yd", "aliases": [ "yard", "yards" ], "description": "International yard.", "system": "International/US", "definition": "1 yd = exactly 0.9144 m", "usage": "Distance and fabric", "transform": "linear", "factor": 0.9144 }, { "id": "fathom", "name": "Fathom", "symbol": "ftm", "aliases": [ "fathom", "fathoms" ], "description": "Six international feet.", "system": "Maritime", "definition": "1 fathom = 1.8288 m", "usage": "Water depth", "transform": "linear", "factor": 1.8288 }, { "id": "rod", "name": "Rod", "symbol": "rd", "aliases": [ "rod", "rods", "perch", "pole" ], "description": "Survey length equal to 16.5 international feet.", "system": "Survey/Imperial", "definition": "1 rod = 5.0292 m", "usage": "Land surveying and historical land measure", "transform": "linear", "factor": 5.0292 }, { "id": "m", "name": "Meter", "symbol": "m", "aliases": [ "meter", "meters", "metre", "metres" ], "description": "SI base unit of length.", "system": "SI", "definition": "1 m = 1 m", "usage": "General length", "transform": "linear", "factor": 1 }, { "id": "chain", "name": "Chain", "symbol": "ch", "aliases": [ "chain", "chains" ], "description": "66 international feet.", "system": "Survey", "definition": "1 chain = 20.1168 m", "usage": "Land surveying", "transform": "linear", "factor": 20.1168 }, { "id": "furlong", "name": "Furlong", "symbol": "fur", "aliases": [ "furlong", "furlongs" ], "description": "Ten chains.", "system": "Imperial", "definition": "1 furlong = 201.168 m", "usage": "Historic and racing distance", "transform": "linear", "factor": 201.168 }, { "id": "km", "name": "Kilometer", "symbol": "km", "aliases": [ "kilometer", "kilometers", "kilometre", "kilometres" ], "description": "One thousand meters.", "system": "SI", "definition": "1 km = 1000 m", "usage": "Road and geographic distance", "transform": "linear", "factor": 1000 }, { "id": "mi", "name": "Mile", "symbol": "mi", "aliases": [ "mile", "miles" ], "description": "International statute mile.", "system": "International/US", "definition": "1 mi = exactly 1609.344 m", "usage": "Road distance", "transform": "linear", "factor": 1609.344 }, { "id": "nmi", "name": "Nautical Mile", "symbol": "nmi", "aliases": [ "nautical mile", "nautical miles", "nmile" ], "description": "International nautical mile.", "system": "Maritime", "definition": "1 nmi = exactly 1852 m", "usage": "Navigation", "transform": "linear", "factor": 1852 }, { "id": "league", "name": "League", "symbol": "lea", "aliases": [ "league", "leagues", "statute league" ], "description": "Conventional land league equal to three international statute miles.", "system": "Historical/Conventional", "definition": "1 league = 3 mi = 4,828.032 m", "usage": "Historical long-distance measure", "transform": "linear", "factor": 4828.032 }, { "id": "au", "name": "Astronomical Unit", "symbol": "AU", "aliases": [ "astronomical unit", "astronomical units" ], "description": "Defined astronomical unit.", "system": "Astronomy", "definition": "1 AU = exactly 149,597,870,700 m", "usage": "Solar-system distance", "transform": "linear", "factor": 149597870700 }, { "id": "ly", "name": "Light-year", "symbol": "ly", "aliases": [ "light year", "light years", "light-year", "light-years" ], "description": "Distance light travels in a Julian year.", "system": "Astronomy", "definition": "1 ly = 9.4607304725808×10¹⁵ m", "usage": "Interstellar distance", "transform": "linear", "factor": 9460730472580800 }, { "id": "pc", "name": "Parsec", "symbol": "pc", "aliases": [ "parsec", "parsecs" ], "description": "Astronomical distance unit.", "system": "Astronomy", "definition": "≈ 3.085677581491367×10¹⁶ m", "usage": "Astronomy", "transform": "linear", "factor": 30856775814913670 } ] }, "mass": { "name": "Mass & Weight", "base": "kg", "dimension": "mass", "description": "Mass units spanning laboratory scales, everyday weights, precious metals and large industrial quantities.", "units": [ { "id": "ug", "name": "Microgram", "symbol": "µg", "aliases": [ "ug", "μg", "microgram", "micrograms" ], "description": "One billionth of a kilogram.", "system": "SI", "definition": "1 µg = 10⁻⁹ kg", "usage": "Very small masses", "transform": "linear", "factor": 1e-9 }, { "id": "mg", "name": "Milligram", "symbol": "mg", "aliases": [ "milligram", "milligrams" ], "description": "One millionth of a kilogram.", "system": "SI", "definition": "1 mg = 10⁻⁶ kg", "usage": "Small masses", "transform": "linear", "factor": 0.000001 }, { "id": "u", "name": "Unified Atomic Mass Unit", "symbol": "u", "aliases": [ "atomic mass unit", "atomic mass units", "unified atomic mass unit", "unified atomic mass units", "dalton", "daltons", "Da" ], "description": "Atomic-scale mass unit approximately equal to one twelfth of a carbon-12 atom mass.", "system": "SI accepted", "definition": "1 u ≈ 1.66053906892×10⁻²⁷ kg", "usage": "Atomic and molecular mass", "transform": "linear", "factor": 1.66053906892e-27 }, { "id": "ng", "name": "Nanogram", "symbol": "ng", "aliases": [ "nanogram", "nanograms" ], "description": "One trillionth of a kilogram.", "system": "SI", "definition": "1 ng = 10⁻¹² kg", "usage": "Laboratory and trace mass", "transform": "linear", "factor": 1e-12 }, { "id": "grain", "name": "Grain", "symbol": "gr", "aliases": [ "grain", "grains" ], "description": "Avoirdupois and troy grain defined as one seven-thousandth of an international pound.", "system": "Avoirdupois/Troy", "definition": "1 gr = exactly 64.79891 mg", "usage": "Ammunition, precious metals and legacy pharmacy", "transform": "linear", "factor": 0.00006479891 }, { "id": "carat", "name": "Carat", "symbol": "ct", "aliases": [ "carat", "carats", "metric carat" ], "description": "Metric carat used for gemstones.", "system": "Metric", "definition": "1 ct = exactly 200 mg", "usage": "Gemstone mass", "transform": "linear", "factor": 0.0002 }, { "id": "g", "name": "Gram", "symbol": "g", "aliases": [ "gram", "grams" ], "description": "One thousandth of a kilogram.", "system": "SI", "definition": "1 g = 0.001 kg", "usage": "Everyday mass", "transform": "linear", "factor": 0.001 }, { "id": "pennyweight", "name": "Pennyweight", "symbol": "dwt", "aliases": [ "pennyweight", "pennyweights" ], "description": "Troy mass unit equal to twenty-four grains.", "system": "Troy", "definition": "1 dwt = exactly 1.55517384 g", "usage": "Precious metals", "transform": "linear", "factor": 0.00155517384 }, { "id": "dram", "name": "Avoirdupois Dram", "symbol": "dr", "aliases": [ "dram", "drams", "avoirdupois dram", "avoirdupois drams" ], "description": "Avoirdupois mass unit equal to one sixteenth of an ounce.", "system": "Avoirdupois", "definition": "1 dr = exactly 1.7718451953125 g", "usage": "Legacy small-mass measure", "transform": "linear", "factor": 0.0017718451953125 }, { "id": "oz", "name": "Ounce", "symbol": "oz", "aliases": [ "ounce", "ounces", "avoirdupois ounce", "avoirdupois ounces" ], "description": "International avoirdupois ounce.", "system": "Avoirdupois", "definition": "1 oz = exactly 28.349523125 g", "usage": "Food and small masses", "transform": "linear", "factor": 0.028349523125 }, { "id": "oz-t", "name": "Troy Ounce", "symbol": "oz t", "aliases": [ "troy ounce", "troy ounces", "ozt", "oz t" ], "description": "Troy mass unit equal to 480 grains.", "system": "Troy", "definition": "1 oz t = exactly 31.1034768 g", "usage": "Gold, silver and precious metals", "transform": "linear", "factor": 0.0311034768 }, { "id": "lb", "name": "Pound", "symbol": "lb", "aliases": [ "lbs", "pound", "pounds" ], "description": "International avoirdupois pound.", "system": "Avoirdupois", "definition": "1 lb = exactly 0.45359237 kg", "usage": "Body and goods mass", "transform": "linear", "factor": 0.45359237 }, { "id": "kg", "name": "Kilogram", "symbol": "kg", "aliases": [ "kilogram", "kilograms", "kilo", "kilos" ], "description": "SI base unit of mass.", "system": "SI", "definition": "1 kg = 1 kg", "usage": "General mass", "transform": "linear", "factor": 1 }, { "id": "stone", "name": "Stone", "symbol": "st", "aliases": [ "stone", "stones" ], "description": "Fourteen international pounds.", "system": "Imperial", "definition": "1 st = 6.35029318 kg", "usage": "Body mass in UK and Ireland", "transform": "linear", "factor": 6.35029318 }, { "id": "slug", "name": "Slug", "symbol": "slug", "aliases": [ "slugs" ], "description": "US engineering mass unit producing one pound-force under one foot per second squared acceleration.", "system": "US engineering", "definition": "1 slug ≈ 14.5939029372 kg", "usage": "Mechanics and engineering", "transform": "linear", "factor": 14.59390293720636 }, { "id": "quintal", "name": "Metric Quintal", "symbol": "q", "aliases": [ "quintal", "quintals", "metric quintal", "metric quintals" ], "description": "Metric mass unit equal to one hundred kilograms.", "system": "Metric", "definition": "1 q = 100 kg", "usage": "Agriculture and commodity mass", "transform": "linear", "factor": 100 }, { "id": "us-ton", "name": "US Ton", "symbol": "short ton", "aliases": [ "us ton", "us tons", "short ton", "short tons" ], "description": "Two thousand international pounds.", "system": "US customary", "definition": "1 short ton = 907.18474 kg", "usage": "Large US masses", "transform": "linear", "factor": 907.18474 }, { "id": "tonne", "name": "Metric Tonne", "symbol": "t", "aliases": [ "tonne", "tonnes", "metric ton", "metric tons" ], "description": "One thousand kilograms.", "system": "SI accepted", "definition": "1 t = 1000 kg", "usage": "Large masses", "transform": "linear", "factor": 1000 }, { "id": "imperial-ton", "name": "Imperial Ton", "symbol": "long ton", "aliases": [ "imperial ton", "imperial tons", "long ton", "long tons" ], "description": "Two thousand two hundred forty international pounds.", "system": "Imperial", "definition": "1 long ton = 1016.0469088 kg", "usage": "Large imperial masses", "transform": "linear", "factor": 1016.0469088 } ] }, "temperature": { "name": "Temperature", "base": "K", "dimension": "temperature", "description": "Temperature scales with affine conversion formulas, including modern and historical scales.", "units": [ { "id": "c", "name": "Celsius", "symbol": "°C", "aliases": [ "c", "celsius", "centigrade", "degree celsius", "degrees celsius" ], "description": "Celsius temperature scale.", "system": "SI derived", "definition": "K = °C + 273.15", "usage": "Weather and science", "transform": "affine", "scale": 1, "offset": 273.15 }, { "id": "f", "name": "Fahrenheit", "symbol": "°F", "aliases": [ "f", "fahrenheit", "degree fahrenheit", "degrees fahrenheit" ], "description": "Fahrenheit temperature scale.", "system": "US customary", "definition": "K = (°F + 459.67) × 5/9", "usage": "Weather in the United States", "transform": "affine", "scale": 0.5555555555555556, "offset": 255.3722222222222 }, { "id": "k", "name": "Kelvin", "symbol": "K", "aliases": [ "kelvin", "kelvins" ], "description": "SI base unit of thermodynamic temperature.", "system": "SI", "definition": "K = K", "usage": "Science and engineering", "transform": "affine", "scale": 1, "offset": 0 }, { "id": "r", "name": "Rankine", "symbol": "°R", "aliases": [ "rankine", "degree rankine", "degrees rankine" ], "description": "Absolute Fahrenheit-based scale.", "system": "Engineering", "definition": "K = °R × 5/9", "usage": "Thermodynamics", "transform": "affine", "scale": 0.5555555555555556, "offset": 0 }, { "id": "reaumur", "name": "Réaumur", "symbol": "°Ré", "aliases": [ "reaumur", "réaumur", "degree reaumur", "degrees reaumur", "degree réaumur", "degrees réaumur" ], "description": "Historical temperature scale with water freezing at 0 °Ré and boiling at 80 °Ré.", "system": "Historical", "definition": "K = °Ré × 5/4 + 273.15", "usage": "Historical scientific texts", "transform": "affine", "scale": 1.25, "offset": 273.15 }, { "id": "romer", "name": "Rømer", "symbol": "°Rø", "aliases": [ "romer", "rømer", "degree romer", "degrees romer", "degree rømer", "degrees rømer" ], "description": "Historical scale with water freezing at 7.5 °Rø and boiling at 60 °Rø.", "system": "Historical", "definition": "°C = (°Rø − 7.5) × 40/21", "usage": "Historical temperature references", "transform": "affine", "scale": 1.9047619047619047, "offset": 258.8642857142857 }, { "id": "delisle", "name": "Delisle", "symbol": "°De", "aliases": [ "delisle", "degree delisle", "degrees delisle" ], "description": "Historical reversed scale where higher values represent colder temperatures.", "system": "Historical", "definition": "°C = 100 − °De × 2/3", "usage": "Historical temperature references", "transform": "affine", "scale": -0.6666666666666666, "offset": 373.15 }, { "id": "newton-temp", "name": "Newton Temperature Scale", "symbol": "°N", "aliases": [ "newton temperature", "newton scale", "degree newton", "degrees newton" ], "description": "Historical Newton temperature scale with water freezing at 0 °N and boiling at 33 °N.", "system": "Historical", "definition": "°C = °N × 100/33", "usage": "Historical scientific references", "transform": "affine", "scale": 3.0303030303030303, "offset": 273.15 } ] }, "volume": { "name": "Volume", "base": "ml", "dimension": "volume", "description": "Metric, cubic, US customary, UK imperial and industrial volume units.", "units": [ { "id": "ml", "name": "Milliliter", "symbol": "mL", "aliases": [ "ml", "milliliter", "milliliters", "millilitre", "millilitres" ], "description": "One cubic centimeter.", "system": "SI accepted", "definition": "1 mL = 1 cm³", "usage": "Small liquid volumes", "transform": "linear", "factor": 1 }, { "id": "cl", "name": "Centiliter", "symbol": "cL", "aliases": [ "cl", "centiliter", "centiliters", "centilitre", "centilitres" ], "description": "Ten milliliters.", "system": "Metric", "definition": "1 cL = 10 mL", "usage": "Beverage volumes", "transform": "linear", "factor": 10 }, { "id": "cc", "name": "Cubic Centimeter", "symbol": "cm³", "aliases": [ "cc", "cm3", "cm^3", "cubic centimeter", "cubic centimeters", "cubic centimetre", "cubic centimetres" ], "description": "Equivalent to one milliliter.", "system": "Metric", "definition": "1 cm³ = 1 mL", "usage": "Engine and medical volume", "transform": "linear", "factor": 1 }, { "id": "in3", "name": "Cubic Inch", "symbol": "in³", "aliases": [ "in3", "in^3", "cu in", "cubic inch", "cubic inches" ], "description": "Volume of a cube one international inch on each side.", "system": "International/US", "definition": "1 in³ = exactly 16.387064 mL", "usage": "Engine displacement and small solid volumes", "transform": "linear", "factor": 16.387064 }, { "id": "tsp-us", "name": "US Teaspoon", "symbol": "US tsp", "aliases": [ "us tsp", "us teaspoon", "us teaspoons", "teaspoon us" ], "description": "US customary teaspoon.", "system": "US customary", "definition": "1 US tsp = 4.92892159375 mL", "usage": "Cooking", "transform": "linear", "factor": 4.92892159375 }, { "id": "tbsp-us", "name": "US Tablespoon", "symbol": "US tbsp", "aliases": [ "us tbsp", "us tablespoon", "us tablespoons", "tablespoon us" ], "description": "Three US teaspoons.", "system": "US customary", "definition": "1 US tbsp = 14.78676478125 mL", "usage": "Cooking", "transform": "linear", "factor": 14.78676478125 }, { "id": "fl-oz-uk", "name": "Imperial Fluid Ounce", "symbol": "Imp fl oz", "aliases": [ "imperial fl oz", "uk fl oz", "imperial fluid ounce", "imperial fluid ounces" ], "description": "UK imperial fluid ounce.", "system": "Imperial", "definition": "1 Imp fl oz = 28.4130625 mL", "usage": "Liquid volume", "transform": "linear", "factor": 28.4130625 }, { "id": "fl-oz-us", "name": "US Fluid Ounce", "symbol": "US fl oz", "aliases": [ "fl oz", "fl oz us", "us fl oz", "fluid ounce", "fluid ounces", "us fluid ounce", "us fluid ounces" ], "description": "US customary fluid ounce.", "system": "US customary", "definition": "1 US fl oz = 29.5735295625 mL", "usage": "Liquid volume", "transform": "linear", "factor": 29.5735295625 }, { "id": "dl", "name": "Deciliter", "symbol": "dL", "aliases": [ "dl", "deciliter", "deciliters", "decilitre", "decilitres" ], "description": "One hundred milliliters.", "system": "Metric", "definition": "1 dL = 100 mL", "usage": "Cooking", "transform": "linear", "factor": 100 }, { "id": "gill-us", "name": "US Gill", "symbol": "US gi", "aliases": [ "us gill", "us gills", "gill us" ], "description": "US customary gill equal to four US fluid ounces.", "system": "US customary", "definition": "1 US gill = 118.29411825 mL", "usage": "Historical beverage and recipe measure", "transform": "linear", "factor": 118.29411825 }, { "id": "gill-uk", "name": "Imperial Gill", "symbol": "Imp gi", "aliases": [ "imperial gill", "imperial gills", "uk gill", "uk gills" ], "description": "Imperial gill equal to five Imperial fluid ounces.", "system": "Imperial", "definition": "1 Imp gill = 142.0653125 mL", "usage": "Historical British liquid measure", "transform": "linear", "factor": 142.0653125 }, { "id": "cup-us", "name": "US Cup", "symbol": "US cup", "aliases": [ "cup", "cups", "us cup", "us cups" ], "description": "Sixteen US tablespoons.", "system": "US customary", "definition": "1 US cup = 236.5882365 mL", "usage": "Cooking", "transform": "linear", "factor": 236.5882365 }, { "id": "pint-us", "name": "US Pint", "symbol": "US pt", "aliases": [ "us pint", "us pints", "pint us" ], "description": "One eighth US gallon.", "system": "US customary", "definition": "1 US pt = 473.176473 mL", "usage": "Liquid volume", "transform": "linear", "factor": 473.176473 }, { "id": "pint-uk", "name": "Imperial Pint", "symbol": "Imp pt", "aliases": [ "imperial pint", "imperial pints", "uk pint", "uk pints" ], "description": "One eighth imperial gallon.", "system": "Imperial", "definition": "1 Imp pt = 568.26125 mL", "usage": "Liquid volume", "transform": "linear", "factor": 568.26125 }, { "id": "quart-us", "name": "US Quart", "symbol": "US qt", "aliases": [ "us quart", "us quarts", "quart us" ], "description": "One quarter US gallon.", "system": "US customary", "definition": "1 US qt = 946.352946 mL", "usage": "Liquid volume", "transform": "linear", "factor": 946.352946 }, { "id": "l", "name": "Liter", "symbol": "L", "aliases": [ "l", "liter", "liters", "litre", "litres" ], "description": "One cubic decimeter.", "system": "SI accepted", "definition": "1 L = 1000 mL", "usage": "General liquids", "transform": "linear", "factor": 1000 }, { "id": "quart-uk", "name": "Imperial Quart", "symbol": "Imp qt", "aliases": [ "imperial quart", "imperial quarts", "uk quart", "uk quarts" ], "description": "One quarter imperial gallon.", "system": "Imperial", "definition": "1 Imp qt = 1.1365225 L", "usage": "Liquid volume", "transform": "linear", "factor": 1136.5225 }, { "id": "gallon-us", "name": "US Gallon", "symbol": "US gal", "aliases": [ "gallon", "gallons", "us gallon", "us gallons", "gal us" ], "description": "US liquid gallon.", "system": "US customary", "definition": "1 US gal = exactly 3.785411784 L", "usage": "Fuel and liquid volume", "transform": "linear", "factor": 3785.411784 }, { "id": "gallon-uk", "name": "Imperial Gallon", "symbol": "Imp gal", "aliases": [ "imperial gallon", "imperial gallons", "uk gallon", "uk gallons" ], "description": "UK imperial gallon.", "system": "Imperial", "definition": "1 Imp gal = exactly 4.54609 L", "usage": "Fuel and liquid volume", "transform": "linear", "factor": 4546.09 }, { "id": "ft3", "name": "Cubic Foot", "symbol": "ft³", "aliases": [ "ft3", "ft^3", "cu ft", "cubic foot", "cubic feet" ], "description": "Volume of a cube one international foot on each side.", "system": "International/US", "definition": "1 ft³ = exactly 28,316.846592 mL", "usage": "Construction, HVAC and storage volume", "transform": "linear", "factor": 28316.846592 }, { "id": "bbl-oil", "name": "Oil Barrel", "symbol": "bbl", "aliases": [ "oil barrel", "oil barrels", "barrel oil", "barrels oil", "petroleum barrel", "petroleum barrels" ], "description": "Petroleum barrel equal to forty-two US liquid gallons.", "system": "Petroleum/US", "definition": "1 bbl = exactly 158.987294928 L", "usage": "Crude oil and petroleum volume", "transform": "linear", "factor": 158987.294928 }, { "id": "yd3", "name": "Cubic Yard", "symbol": "yd³", "aliases": [ "yd3", "yd^3", "cu yd", "cubic yard", "cubic yards" ], "description": "Volume of a cube one international yard on each side.", "system": "International/US", "definition": "1 yd³ = exactly 764.554857984 L", "usage": "Concrete, soil and bulk materials", "transform": "linear", "factor": 764554.857984 }, { "id": "m3", "name": "Cubic Meter", "symbol": "m³", "aliases": [ "m3", "m^3", "cubic meter", "cubic meters", "cubic metre", "cubic metres" ], "description": "SI-derived cubic meter.", "system": "SI", "definition": "1 m³ = 1,000,000 mL", "usage": "Large volume", "transform": "linear", "factor": 1000000 }, { "id": "stere", "name": "Stere", "symbol": "st", "aliases": [ "stere", "steres", "stère", "stères" ], "description": "Metric historical volume unit equal to one cubic meter.", "system": "Metric historical", "definition": "1 stere = 1 m³ = 1,000 L", "usage": "Firewood volume", "transform": "linear", "factor": 1000000 }, { "id": "cord", "name": "Cord", "symbol": "cord", "aliases": [ "cords", "wood cord", "wood cords" ], "description": "Stacked firewood volume equal to 128 cubic feet.", "system": "US customary", "definition": "1 cord = exactly 128 ft³ ≈ 3.624556363776 m³", "usage": "Firewood volume", "transform": "linear", "factor": 3624556.363776 } ] }, "area": { "name": "Area", "base": "m2", "dimension": "area", "description": "Surface area units from microscopic scientific scales through land surveying and geographic areas.", "units": [ { "id": "mm2", "name": "Square Millimeter", "symbol": "mm²", "aliases": [ "mm2", "mm^2", "square millimeter", "square millimeters", "square millimetre", "square millimetres" ], "description": "Square millimeter.", "system": "SI", "definition": "1 mm² = 10⁻⁶ m²", "usage": "Small areas", "transform": "linear", "factor": 0.000001 }, { "id": "cm2", "name": "Square Centimeter", "symbol": "cm²", "aliases": [ "cm2", "cm^2", "square centimeter", "square centimeters", "square centimetre", "square centimetres" ], "description": "Square centimeter.", "system": "SI", "definition": "1 cm² = 10⁻⁴ m²", "usage": "Small areas", "transform": "linear", "factor": 0.0001 }, { "id": "barn", "name": "Barn", "symbol": "b", "aliases": [ "barn", "barns" ], "description": "Very small area unit used in nuclear and particle physics.", "system": "Scientific", "definition": "1 b = 10⁻²⁸ m²", "usage": "Nuclear cross sections", "transform": "linear", "factor": 1e-28 }, { "id": "in2", "name": "Square Inch", "symbol": "in²", "aliases": [ "in2", "in^2", "square inch", "square inches" ], "description": "Square international inch.", "system": "International", "definition": "1 in² = 0.00064516 m²", "usage": "Small areas", "transform": "linear", "factor": 0.00064516 }, { "id": "ft2", "name": "Square Foot", "symbol": "ft²", "aliases": [ "ft2", "ft^2", "sq ft", "square foot", "square feet" ], "description": "Square international foot.", "system": "International", "definition": "1 ft² = 0.09290304 m²", "usage": "Real estate", "transform": "linear", "factor": 0.09290304 }, { "id": "m2", "name": "Square Meter", "symbol": "m²", "aliases": [ "m2", "m^2", "square meter", "square meters", "square metre", "square metres" ], "description": "SI-derived area unit.", "system": "SI", "definition": "1 m² = 1 m²", "usage": "Floor and land area", "transform": "linear", "factor": 1 }, { "id": "yd2", "name": "Square Yard", "symbol": "yd²", "aliases": [ "yd2", "yd^2", "sq yd", "square yard", "square yards" ], "description": "Square international yard.", "system": "International", "definition": "1 yd² = 0.83612736 m²", "usage": "Land and fabric", "transform": "linear", "factor": 0.83612736 }, { "id": "sq-rod", "name": "Square Rod", "symbol": "rd²", "aliases": [ "square rod", "square rods", "square perch", "square perches" ], "description": "Area of a square one international rod on each side.", "system": "Survey/Imperial", "definition": "1 square rod = 25.29285264 m²", "usage": "Historical land surveying", "transform": "linear", "factor": 25.29285264 }, { "id": "are", "name": "Are", "symbol": "a", "aliases": [ "are", "ares" ], "description": "Metric land-area unit equal to one hundred square meters.", "system": "Metric", "definition": "1 a = 100 m²", "usage": "Land area", "transform": "linear", "factor": 100 }, { "id": "sq-chain", "name": "Square Chain", "symbol": "ch²", "aliases": [ "square chain", "square chains" ], "description": "Area of a square one international chain on each side.", "system": "Survey/Imperial", "definition": "1 square chain = 404.68564224 m²", "usage": "Land surveying", "transform": "linear", "factor": 404.68564224 }, { "id": "rood", "name": "Rood", "symbol": "rood", "aliases": [ "roods" ], "description": "Historical land-area unit equal to one quarter of an international acre.", "system": "Imperial historical", "definition": "1 rood = 1,011.7141056 m²", "usage": "Historical land area", "transform": "linear", "factor": 1011.7141056 }, { "id": "acre", "name": "Acre", "symbol": "acre", "aliases": [ "acres" ], "description": "International acre.", "system": "International", "definition": "1 acre = 4046.8564224 m²", "usage": "Land area", "transform": "linear", "factor": 4046.8564224 }, { "id": "ha", "name": "Hectare", "symbol": "ha", "aliases": [ "hectare", "hectares" ], "description": "Ten thousand square meters.", "system": "Metric", "definition": "1 ha = 10,000 m²", "usage": "Land area", "transform": "linear", "factor": 10000 }, { "id": "km2", "name": "Square Kilometer", "symbol": "km²", "aliases": [ "km2", "km^2", "square kilometer", "square kilometers", "square kilometre", "square kilometres" ], "description": "One million square meters.", "system": "SI", "definition": "1 km² = 1,000,000 m²", "usage": "Geographic area", "transform": "linear", "factor": 1000000 }, { "id": "mi2", "name": "Square Mile", "symbol": "mi²", "aliases": [ "mi2", "mi^2", "sq mi", "square mile", "square miles" ], "description": "Square international mile.", "system": "International", "definition": "1 mi² = 2,589,988.110336 m²", "usage": "Geographic area", "transform": "linear", "factor": 2589988.110336 } ] }, "speed": { "name": "Speed", "base": "mps", "dimension": "speed", "description": "Deterministic linear speed units. Mach is excluded as a fixed unit because the local speed of sound depends on medium and conditions.", "units": [ { "id": "mps", "name": "Meters per Second", "symbol": "m/s", "aliases": [ "m/s", "meter per second", "meters per second", "metre per second", "metres per second" ], "description": "SI-derived speed unit.", "system": "SI", "definition": "1 m/s = 1 m/s", "usage": "Physics and engineering", "transform": "linear", "factor": 1 }, { "id": "kmh", "name": "Kilometers per Hour", "symbol": "km/h", "aliases": [ "km/h", "kph", "kmph", "kilometer per hour", "kilometers per hour", "kilometre per hour", "kilometres per hour" ], "description": "Metric road speed.", "system": "Metric", "definition": "1 km/h = 0.277777… m/s", "usage": "Road speed", "transform": "linear", "factor": 0.2777777777777778 }, { "id": "mph", "name": "Miles per Hour", "symbol": "mph", "aliases": [ "mile per hour", "miles per hour" ], "description": "Road speed in miles per hour.", "system": "US/UK", "definition": "1 mph = 0.44704 m/s", "usage": "Road speed", "transform": "linear", "factor": 0.44704 }, { "id": "fps", "name": "Feet per Second", "symbol": "ft/s", "aliases": [ "ft/s", "foot per second", "feet per second" ], "description": "Feet traveled per second.", "system": "International", "definition": "1 ft/s = 0.3048 m/s", "usage": "Engineering", "transform": "linear", "factor": 0.3048 }, { "id": "cmps", "name": "Centimeters per Second", "symbol": "cm/s", "aliases": [ "cm/s", "centimeter per second", "centimeters per second", "centimetre per second", "centimetres per second" ], "description": "One hundredth of a meter per second.", "system": "SI", "definition": "1 cm/s = 0.01 m/s", "usage": "Laboratory and slow motion", "transform": "linear", "factor": 0.01 }, { "id": "knot", "name": "Knot", "symbol": "kn", "aliases": [ "knot", "knots", "kt", "kts" ], "description": "One nautical mile per hour.", "system": "Maritime/Aviation", "definition": "1 kn = 1852/3600 m/s", "usage": "Navigation", "transform": "linear", "factor": 0.5144444444444445 }, { "id": "c", "name": "Speed of Light in Vacuum", "symbol": "c", "aliases": [ "speed of light", "speed of light in vacuum", "lightspeed" ], "description": "Defined speed of light in vacuum.", "system": "SI defining constant", "definition": "c = exactly 299,792,458 m/s", "usage": "Relativity and physics reference", "transform": "linear", "factor": 299792458 } ] }, "acceleration": { "name": "Acceleration", "base": "mps2", "dimension": "acceleration", "description": "Linear acceleration units used in physics, engineering, navigation and vehicle performance.", "units": [ { "id": "mps2", "name": "Meter per Second Squared", "symbol": "m/s²", "aliases": [ "m/s2", "meter per second squared", "meters per second squared", "metre per second squared", "metres per second squared" ], "description": "SI unit of acceleration.", "system": "SI", "definition": "1 m/s² = 1 m/s²", "usage": "Physics and engineering", "transform": "linear", "factor": 1 }, { "id": "ftps2", "name": "Foot per Second Squared", "symbol": "ft/s²", "aliases": [ "ft/s2", "foot per second squared", "feet per second squared" ], "description": "Imperial/US customary acceleration unit.", "system": "Imperial/US customary", "definition": "1 ft/s² = 0.3048 m/s²", "usage": "Engineering and motion", "transform": "linear", "factor": 0.3048 }, { "id": "inps2", "name": "Inch per Second Squared", "symbol": "in/s²", "aliases": [ "in/s2", "inch per second squared", "inches per second squared" ], "description": "Acceleration expressed in inches per second per second.", "system": "Imperial/US customary", "definition": "1 in/s² = 0.0254 m/s²", "usage": "Mechanical engineering", "transform": "linear", "factor": 0.0254 }, { "id": "g0", "name": "Standard Gravity", "symbol": "g₀", "aliases": [ "g0", "standard gravity", "gravity", "gee" ], "description": "Conventional standard acceleration due to gravity.", "system": "Conventional", "definition": "1 g₀ = 9.80665 m/s²", "usage": "Aerospace, vehicles and human acceleration", "transform": "linear", "factor": 9.80665 }, { "id": "gal", "name": "Gal", "symbol": "Gal", "aliases": [ "galileo", "gals" ], "description": "CGS acceleration unit equal to one centimeter per second squared.", "system": "CGS", "definition": "1 Gal = 0.01 m/s²", "usage": "Geophysics and gravimetry", "transform": "linear", "factor": 0.01 }, { "id": "knot-s", "name": "Knot per Second", "symbol": "kn/s", "aliases": [ "knot per second", "knots per second", "kt/s" ], "description": "Acceleration that changes speed by one knot each second.", "system": "Maritime/Aviation", "definition": "1 kn/s = 0.5144444444444445 m/s²", "usage": "Navigation and vehicle acceleration", "transform": "linear", "factor": 0.5144444444444445 } ] }, "pressure": { "name": "Pressure", "base": "pa", "dimension": "pressure", "description": "Pressure units used in engineering, weather, tires, vacuum, medicine and fluid columns.", "units": [ { "id": "pa", "name": "Pascal", "symbol": "Pa", "aliases": [ "pascal", "pascals" ], "description": "SI pressure unit.", "system": "SI", "definition": "1 Pa = 1 N/m²", "usage": "Engineering", "transform": "linear", "factor": 1 }, { "id": "kpa", "name": "Kilopascal", "symbol": "kPa", "aliases": [ "kilopascal", "kilopascals" ], "description": "One thousand pascals.", "system": "SI", "definition": "1 kPa = 1000 Pa", "usage": "Tire, weather and engineering pressure", "transform": "linear", "factor": 1000 }, { "id": "hpa", "name": "Hectopascal", "symbol": "hPa", "aliases": [ "hectopascal", "hectopascals" ], "description": "One hundred pascals; numerically equal to one millibar.", "system": "SI", "definition": "1 hPa = 100 Pa", "usage": "Meteorology and atmospheric pressure", "transform": "linear", "factor": 100 }, { "id": "mpa", "name": "Megapascal", "symbol": "MPa", "aliases": [ "megapascal", "megapascals" ], "description": "One million pascals.", "system": "SI", "definition": "1 MPa = 10⁶ Pa", "usage": "Materials and engineering", "transform": "linear", "factor": 1000000 }, { "id": "gpa", "name": "Gigapascal", "symbol": "GPa", "aliases": [ "gigapascal", "gigapascals" ], "description": "One billion pascals.", "system": "SI", "definition": "1 GPa = 10⁹ Pa", "usage": "Elastic modulus and high-pressure engineering", "transform": "linear", "factor": 1000000000 }, { "id": "bar", "name": "Bar", "symbol": "bar", "aliases": [ "bars" ], "description": "Metric pressure unit equal to one hundred kilopascals.", "system": "Metric", "definition": "1 bar = exactly 100,000 Pa", "usage": "Tires, hydraulics and industrial pressure", "transform": "linear", "factor": 100000 }, { "id": "mbar", "name": "Millibar", "symbol": "mbar", "aliases": [ "millibar", "millibars" ], "description": "One thousandth of a bar.", "system": "Metric", "definition": "1 mbar = 100 Pa", "usage": "Weather", "transform": "linear", "factor": 100 }, { "id": "barye", "name": "Barye", "symbol": "Ba", "aliases": [ "barye", "baryes" ], "description": "CGS pressure unit equal to one dyne per square centimeter.", "system": "CGS", "definition": "1 Ba = 0.1 Pa", "usage": "Legacy scientific pressure", "transform": "linear", "factor": 0.1 }, { "id": "psi", "name": "Pounds per Square Inch", "symbol": "psi", "aliases": [ "pound per square inch", "pounds per square inch" ], "description": "Pound-force per square inch.", "system": "US customary", "definition": "1 psi ≈ 6894.757293168 Pa", "usage": "Tires and engineering", "transform": "linear", "factor": 6894.757293168 }, { "id": "atm", "name": "Standard Atmosphere", "symbol": "atm", "aliases": [ "atmosphere", "atmospheres", "standard atmosphere" ], "description": "Defined standard atmosphere.", "system": "Standard", "definition": "1 atm = exactly 101325 Pa", "usage": "Reference pressure", "transform": "linear", "factor": 101325 }, { "id": "at", "name": "Technical Atmosphere", "symbol": "at", "aliases": [ "technical atmosphere", "technical atmospheres" ], "description": "Legacy gravitational pressure unit equal to one kilogram-force per square centimeter.", "system": "Metric gravitational", "definition": "1 at = exactly 98,066.5 Pa", "usage": "Legacy engineering pressure", "transform": "linear", "factor": 98066.5 }, { "id": "torr", "name": "Torr", "symbol": "Torr", "aliases": [ "torrs" ], "description": "One seven-hundred-sixtieth of a standard atmosphere.", "system": "Vacuum", "definition": "1 Torr = 101325/760 Pa", "usage": "Vacuum", "transform": "linear", "factor": 133.32236842105263 }, { "id": "mmhg", "name": "Millimeters of Mercury", "symbol": "mmHg", "aliases": [ "mm hg", "millimeter mercury", "millimeters mercury" ], "description": "Conventional mercury-column pressure unit.", "system": "Medical", "definition": "1 mmHg ≈ 133.322387415 Pa", "usage": "Blood pressure", "transform": "linear", "factor": 133.322387415 }, { "id": "cmhg", "name": "Centimeters of Mercury", "symbol": "cmHg", "aliases": [ "cm hg", "centimeter mercury", "centimeters mercury" ], "description": "Mercury-column pressure equal to ten conventional millimeters of mercury.", "system": "Conventional", "definition": "1 cmHg ≈ 1,333.22387415 Pa", "usage": "Laboratory and legacy pressure", "transform": "linear", "factor": 1333.22387415 }, { "id": "inhg", "name": "Inches of Mercury", "symbol": "inHg", "aliases": [ "in hg", "inch mercury", "inches mercury" ], "description": "Conventional mercury-column pressure unit.", "system": "Aviation/Weather", "definition": "1 inHg ≈ 3386.389 Pa", "usage": "Barometric pressure", "transform": "linear", "factor": 3386.389 }, { "id": "inh2o", "name": "Inches of Water", "symbol": "inH₂O", "aliases": [ "inH2O", "in h2o", "inch of water", "inches of water", "inch water", "inches water" ], "description": "Conventional water-column pressure based on water at 4 °C.", "system": "Conventional", "definition": "1 inH₂O ≈ 249.08891 Pa", "usage": "HVAC and low-pressure measurement", "transform": "linear", "factor": 249.08891 } ] }, "energy": { "name": "Energy", "base": "j", "dimension": "energy", "description": "Mechanical, thermal, electrical, particle-physics and large-scale energy units.", "units": [ { "id": "j", "name": "Joule", "symbol": "J", "aliases": [ "joule", "joules" ], "description": "SI energy unit.", "system": "SI", "definition": "1 J = 1 N·m", "usage": "General energy", "transform": "linear", "factor": 1 }, { "id": "kj", "name": "Kilojoule", "symbol": "kJ", "aliases": [ "kilojoule", "kilojoules" ], "description": "One thousand joules.", "system": "SI", "definition": "1 kJ = 1000 J", "usage": "Food and engineering", "transform": "linear", "factor": 1000 }, { "id": "erg", "name": "Erg", "symbol": "erg", "aliases": [ "ergs" ], "description": "CGS energy unit.", "system": "CGS", "definition": "1 erg = 10⁻⁷ J", "usage": "Legacy physics and astronomy", "transform": "linear", "factor": 1e-7 }, { "id": "ev", "name": "Electronvolt", "symbol": "eV", "aliases": [ "electronvolt", "electronvolts" ], "description": "Energy gained by one elementary charge through one volt.", "system": "SI accepted", "definition": "1 eV = exactly 1.602176634×10⁻¹⁹ J", "usage": "Atomic physics", "transform": "linear", "factor": 1.602176634e-19 }, { "id": "mev", "name": "Megaelectronvolt", "symbol": "MeV", "aliases": [ "megaelectronvolt", "megaelectronvolts" ], "description": "One million electronvolts.", "system": "Scientific", "definition": "1 MeV = exactly 1.602176634×10⁻¹³ J", "usage": "Nuclear and particle physics", "transform": "linear", "factor": 1.602176634e-13 }, { "id": "gev", "name": "Gigaelectronvolt", "symbol": "GeV", "aliases": [ "gigaelectronvolt", "gigaelectronvolts" ], "description": "One billion electronvolts.", "system": "Scientific", "definition": "1 GeV = exactly 1.602176634×10⁻¹⁰ J", "usage": "Particle physics", "transform": "linear", "factor": 1.602176634e-10 }, { "id": "cal", "name": "Calorie", "symbol": "cal", "aliases": [ "calorie", "calories", "small calorie", "small calories" ], "description": "Thermochemical calorie.", "system": "Thermochemical", "definition": "1 cal = exactly 4.184 J", "usage": "Heat", "transform": "linear", "factor": 4.184 }, { "id": "kcal", "name": "Kilocalorie", "symbol": "kcal", "aliases": [ "kilocalorie", "kilocalories", "food calorie", "food calories" ], "description": "One thousand thermochemical calories.", "system": "Thermochemical", "definition": "1 kcal = exactly 4184 J", "usage": "Food energy", "transform": "linear", "factor": 4184 }, { "id": "ft-lb", "name": "Foot-pound", "symbol": "ft·lb", "aliases": [ "ft lb", "foot pound", "foot pounds", "foot-pound", "foot-pounds" ], "description": "Foot pound-force energy.", "system": "US customary", "definition": "1 ft·lbf ≈ 1.3558179483314004 J", "usage": "Mechanical work", "transform": "linear", "factor": 1.3558179483314003 }, { "id": "btu", "name": "BTU (IT)", "symbol": "BTU", "aliases": [ "btu", "british thermal unit", "british thermal units" ], "description": "International Table British thermal unit.", "system": "Thermal", "definition": "1 BTU(IT) = 1055.05585262 J", "usage": "Heating and cooling", "transform": "linear", "factor": 1055.05585262 }, { "id": "wh", "name": "Watt-hour", "symbol": "Wh", "aliases": [ "watt hour", "watt hours", "watt-hour", "watt-hours" ], "description": "Power integrated over one hour.", "system": "Electrical", "definition": "1 Wh = 3600 J", "usage": "Electrical energy", "transform": "linear", "factor": 3600 }, { "id": "mj", "name": "Megajoule", "symbol": "MJ", "aliases": [ "megajoule", "megajoules" ], "description": "One million joules.", "system": "SI", "definition": "1 MJ = 10⁶ J", "usage": "Large energy", "transform": "linear", "factor": 1000000 }, { "id": "kwh", "name": "Kilowatt-hour", "symbol": "kWh", "aliases": [ "kilowatt hour", "kilowatt hours", "kilowatt-hour", "kilowatt-hours" ], "description": "One thousand watt-hours.", "system": "Electrical", "definition": "1 kWh = 3.6 MJ", "usage": "Electricity billing", "transform": "linear", "factor": 3600000 }, { "id": "mwh", "name": "Megawatt-hour", "symbol": "MWh", "aliases": [ "megawatt hour", "megawatt hours", "megawatt-hour", "megawatt-hours" ], "description": "One thousand kilowatt-hours.", "system": "Electrical", "definition": "1 MWh = 3.6×10⁹ J", "usage": "Grid-scale electrical energy", "transform": "linear", "factor": 3600000000 }, { "id": "ton-tnt", "name": "Ton of TNT", "symbol": "t TNT", "aliases": [ "ton tnt", "ton of tnt", "tons of tnt", "tonne tnt equivalent" ], "description": "Conventional explosive-energy equivalent.", "system": "Conventional", "definition": "1 ton TNT = exactly 4.184×10⁹ J", "usage": "Explosive energy comparison", "transform": "linear", "factor": 4184000000 }, { "id": "therm-us", "name": "US Therm", "symbol": "therm", "aliases": [ "therm", "therms", "us therm", "us therms" ], "description": "US customary energy unit equal to one hundred thousand International Table BTU.", "system": "US customary", "definition": "1 therm = 100,000 BTU(IT) = 105,505,585.262 J", "usage": "Natural-gas billing", "transform": "linear", "factor": 105505585.262 }, { "id": "quad", "name": "Quad", "symbol": "quad", "aliases": [ "quads" ], "description": "Large energy unit equal to one quadrillion International Table BTU.", "system": "US energy", "definition": "1 quad = 10¹⁵ BTU(IT) = 1.05505585262×10¹⁸ J", "usage": "National and global energy statistics", "transform": "linear", "factor": 1055055852620000000 } ] }, "power": { "name": "Power", "base": "w", "dimension": "power", "description": "Rate of energy transfer across electrical, mechanical, thermal and HVAC systems.", "units": [ { "id": "w", "name": "Watt", "symbol": "W", "aliases": [ "watt", "watts" ], "description": "SI power unit.", "system": "SI", "definition": "1 W = 1 J/s", "usage": "General power", "transform": "linear", "factor": 1 }, { "id": "kw", "name": "Kilowatt", "symbol": "kW", "aliases": [ "kilowatt", "kilowatts" ], "description": "One thousand watts.", "system": "SI", "definition": "1 kW = 1000 W", "usage": "Electrical and mechanical power", "transform": "linear", "factor": 1000 }, { "id": "mwatt", "name": "Milliwatt", "symbol": "mW", "aliases": [ "milliwatt", "milliwatts" ], "description": "One thousandth of a watt.", "system": "SI", "definition": "1 mW = 0.001 W", "usage": "Electronics and low-power devices", "transform": "linear", "factor": 0.001 }, { "id": "erg-s", "name": "Erg per Second", "symbol": "erg/s", "aliases": [ "erg per second", "ergs per second" ], "description": "CGS power unit.", "system": "CGS", "definition": "1 erg/s = 10⁻⁷ W", "usage": "Legacy scientific power", "transform": "linear", "factor": 1e-7 }, { "id": "cal-s", "name": "Calorie per Second", "symbol": "cal/s", "aliases": [ "calorie per second", "calories per second" ], "description": "Thermochemical calorie per second.", "system": "Thermochemical", "definition": "1 cal/s = exactly 4.184 W", "usage": "Heat-transfer calculations", "transform": "linear", "factor": 4.184 }, { "id": "ftlb-min", "name": "Foot-pound per Minute", "symbol": "ft·lbf/min", "aliases": [ "foot pound per minute", "foot pounds per minute", "ft lb per minute" ], "description": "Mechanical power based on foot-pound force per minute.", "system": "US customary", "definition": "1 ft·lbf/min ≈ 0.02259696580552334 W", "usage": "Legacy mechanical power", "transform": "linear", "factor": 0.02259696580552334 }, { "id": "btu-h", "name": "BTU per Hour", "symbol": "BTU/h", "aliases": [ "btu/h", "btu per hour", "btus per hour" ], "description": "International Table BTU per hour.", "system": "Thermal", "definition": "1 BTU/h ≈ 0.2930710701722222 W", "usage": "HVAC", "transform": "linear", "factor": 0.2930710701722222 }, { "id": "hp-metric", "name": "Metric Horsepower", "symbol": "PS", "aliases": [ "metric horsepower", "ps", "cv" ], "description": "Metric horsepower (Pferdestärke).", "system": "Metric", "definition": "1 PS = 735.49875 W", "usage": "Engines in some markets", "transform": "linear", "factor": 735.49875 }, { "id": "hp-mech", "name": "Mechanical Horsepower", "symbol": "hp", "aliases": [ "horsepower", "mechanical horsepower", "hp mechanical" ], "description": "Mechanical horsepower.", "system": "US customary", "definition": "1 hp ≈ 745.6998715822702 W", "usage": "Engines", "transform": "linear", "factor": 745.6998715822702 }, { "id": "ton-ref", "name": "Ton of Refrigeration", "symbol": "TR", "aliases": [ "ton refrigeration", "tons refrigeration", "ton of refrigeration", "tons of refrigeration" ], "description": "Cooling power convention equal to twelve thousand International Table BTU per hour.", "system": "HVAC", "definition": "1 TR ≈ 3,516.8528420667 W", "usage": "Air conditioning and refrigeration", "transform": "linear", "factor": 3516.852842066666 }, { "id": "mw", "name": "Megawatt", "symbol": "MW", "aliases": [ "megawatt", "megawatts" ], "description": "One million watts.", "system": "SI", "definition": "1 MW = 10⁶ W", "usage": "Grid and industrial power", "transform": "linear", "factor": 1000000 }, { "id": "gw", "name": "Gigawatt", "symbol": "GW", "aliases": [ "gigawatt", "gigawatts" ], "description": "One billion watts.", "system": "SI", "definition": "1 GW = 10⁹ W", "usage": "Power stations and grid-scale generation", "transform": "linear", "factor": 1000000000 } ] }, "force": { "name": "Force", "base": "n", "dimension": "force", "description": "Force units used in SI, CGS, US customary and legacy engineering systems.", "units": [ { "id": "n", "name": "Newton", "symbol": "N", "aliases": [ "newton", "newtons" ], "description": "SI force unit.", "system": "SI", "definition": "1 N = 1 kg·m/s²", "usage": "Physics and engineering", "transform": "linear", "factor": 1 }, { "id": "kn", "name": "Kilonewton", "symbol": "kN", "aliases": [ "kilonewton", "kilonewtons" ], "description": "One thousand newtons.", "system": "SI", "definition": "1 kN = 1000 N", "usage": "Structural engineering", "transform": "linear", "factor": 1000 }, { "id": "dyne", "name": "Dyne", "symbol": "dyn", "aliases": [ "dyne", "dynes" ], "description": "CGS force unit.", "system": "CGS", "definition": "1 dyn = 10⁻⁵ N", "usage": "Legacy scientific use", "transform": "linear", "factor": 0.00001 }, { "id": "poundal", "name": "Poundal", "symbol": "pdl", "aliases": [ "poundal", "poundals" ], "description": "FPS absolute force unit equal to one pound mass accelerated by one foot per second squared.", "system": "FPS", "definition": "1 pdl = exactly 0.138254954376 N", "usage": "Legacy mechanics", "transform": "linear", "factor": 0.138254954376 }, { "id": "ozf", "name": "Ounce-force", "symbol": "ozf", "aliases": [ "ounce force", "ounces force", "ounce-force", "ounces-force" ], "description": "One sixteenth of an international pound-force.", "system": "US customary", "definition": "1 ozf ≈ 0.2780138509537812 N", "usage": "Small mechanical forces", "transform": "linear", "factor": 0.2780138509537812 }, { "id": "lbf", "name": "Pound-force", "symbol": "lbf", "aliases": [ "pound force", "pounds force", "pound-force", "pounds-force" ], "description": "Force due to standard gravity on one international pound mass.", "system": "US customary", "definition": "1 lbf = 4.4482216152605 N", "usage": "Engineering", "transform": "linear", "factor": 4.4482216152605 }, { "id": "kgf", "name": "Kilogram-force", "symbol": "kgf", "aliases": [ "kilogram force", "kilograms force", "kilopond" ], "description": "Force due to standard gravity on one kilogram.", "system": "Metric gravitational", "definition": "1 kgf = 9.80665 N", "usage": "Legacy engineering", "transform": "linear", "factor": 9.80665 }, { "id": "sthene", "name": "Sthene", "symbol": "sn", "aliases": [ "sthene", "sthenes" ], "description": "MTS-system force unit equal to one thousand newtons.", "system": "MTS historical", "definition": "1 sn = 1000 N", "usage": "Historical engineering", "transform": "linear", "factor": 1000 }, { "id": "kip", "name": "Kip-force", "symbol": "kip", "aliases": [ "kip", "kips", "kip force", "kip-force" ], "description": "US engineering force unit equal to one thousand pound-force.", "system": "US customary", "definition": "1 kip = 1000 lbf = 4448.2216152605 N", "usage": "Structural engineering", "transform": "linear", "factor": 4448.2216152605 }, { "id": "mn", "name": "Meganewton", "symbol": "MN", "aliases": [ "meganewton", "meganewtons" ], "description": "One million newtons.", "system": "SI", "definition": "1 MN = 10⁶ N", "usage": "Large structural and mechanical forces", "transform": "linear", "factor": 1000000 } ] }, "torque": { "name": "Torque", "base": "nm", "dimension": "torque", "description": "Moment of force units used in mechanical, automotive and engineering work.", "units": [ { "id": "nm", "name": "Newton-meter", "symbol": "N·m", "aliases": [ "n m", "n*m", "newton meter", "newton meters", "newton-metre", "newton-metres" ], "description": "SI torque unit.", "system": "SI", "definition": "1 N·m = 1 N·m", "usage": "Mechanical torque", "transform": "linear", "factor": 1 }, { "id": "ncm", "name": "Newton-centimeter", "symbol": "N·cm", "aliases": [ "n cm", "n*cm", "newton centimeter", "newton centimeters" ], "description": "One hundredth newton-meter.", "system": "SI", "definition": "1 N·cm = 0.01 N·m", "usage": "Small torque", "transform": "linear", "factor": 0.01 }, { "id": "lbft", "name": "Pound-foot", "symbol": "lb·ft", "aliases": [ "lb ft", "lb-ft", "lbf ft", "pound foot", "pound feet" ], "description": "Pound-force foot torque.", "system": "US customary", "definition": "1 lb·ft ≈ 1.3558179483314004 N·m", "usage": "Automotive torque", "transform": "linear", "factor": 1.3558179483314003 }, { "id": "lbin", "name": "Pound-inch", "symbol": "lb·in", "aliases": [ "lb in", "lb-in", "lbf in", "pound inch", "pound inches" ], "description": "Pound-force inch torque.", "system": "US customary", "definition": "1 lb·in ≈ 0.1129848290276167 N·m", "usage": "Fasteners", "transform": "linear", "factor": 0.1129848290276167 }, { "id": "kgfm", "name": "Kilogram-force Meter", "symbol": "kgf·m", "aliases": [ "kgf m", "kgf*m", "kilogram force meter" ], "description": "Kilogram-force meter.", "system": "Metric gravitational", "definition": "1 kgf·m = 9.80665 N·m", "usage": "Legacy torque", "transform": "linear", "factor": 9.80665 }, { "id": "knm", "name": "Kilonewton-meter", "symbol": "kN·m", "aliases": [ "kn m", "kn*m", "kilonewton meter", "kilonewton meters" ], "description": "One thousand newton-meters.", "system": "SI", "definition": "1 kN·m = 1000 N·m", "usage": "Structural and heavy mechanical torque", "transform": "linear", "factor": 1000 }, { "id": "ozin", "name": "Ounce-inch", "symbol": "oz·in", "aliases": [ "oz in", "oz-in", "ounce inch", "ounce inches", "ounce-force inch" ], "description": "Ounce-force inch torque.", "system": "US customary", "definition": "1 oz·in ≈ 0.00706155181422604 N·m", "usage": "Small fasteners and instruments", "transform": "linear", "factor": 0.00706155181422604 }, { "id": "dyncm", "name": "Dyne-centimeter", "symbol": "dyn·cm", "aliases": [ "dyn cm", "dyne centimeter", "dyne-centimeter" ], "description": "CGS torque unit.", "system": "CGS", "definition": "1 dyn·cm = 10⁻⁷ N·m", "usage": "Legacy scientific torque", "transform": "linear", "factor": 1e-7 } ] }, "density": { "name": "Density", "base": "kgm3", "dimension": "density", "description": "Mass per unit volume.", "units": [ { "id": "kgm3", "name": "Kilograms per Cubic Meter", "symbol": "kg/m³", "aliases": [ "kg/m3", "kg m-3", "kilogram per cubic meter", "kilograms per cubic meter" ], "description": "SI density unit.", "system": "SI", "definition": "1 kg/m³ = 1 kg/m³", "usage": "Materials and fluids", "transform": "linear", "factor": 1 }, { "id": "gcm3", "name": "Grams per Cubic Centimeter", "symbol": "g/cm³", "aliases": [ "g/cm3", "gram per cubic centimeter", "grams per cubic centimeter" ], "description": "Common material density unit.", "system": "Metric", "definition": "1 g/cm³ = 1000 kg/m³", "usage": "Material density", "transform": "linear", "factor": 1000 }, { "id": "lbft3", "name": "Pounds per Cubic Foot", "symbol": "lb/ft³", "aliases": [ "lb/ft3", "pound per cubic foot", "pounds per cubic foot" ], "description": "Avoirdupois pounds per cubic foot.", "system": "US customary", "definition": "1 lb/ft³ ≈ 16.01846337396 kg/m³", "usage": "Materials/HVAC", "transform": "linear", "factor": 16.01846337396014 }, { "id": "lbgal-us", "name": "Pounds per US Gallon", "symbol": "lb/US gal", "aliases": [ "lb/gal", "lb/us gal", "pound per gallon", "pounds per gallon" ], "description": "Avoirdupois pounds per US liquid gallon.", "system": "US customary", "definition": "1 lb/US gal ≈ 119.8264273169 kg/m³", "usage": "Fluids", "transform": "linear", "factor": 119.8264273168966 } ] }, "frequency": { "name": "Frequency", "base": "hz", "dimension": "frequency", "description": "Cycles, events and angular frequency per second.", "units": [ { "id": "hz", "name": "Hertz", "symbol": "Hz", "aliases": [ "hertz" ], "description": "One cycle per second.", "system": "SI", "definition": "1 Hz = 1 s⁻¹", "usage": "Signals and cycles", "transform": "linear", "factor": 1 }, { "id": "khz", "name": "Kilohertz", "symbol": "kHz", "aliases": [ "kilohertz" ], "description": "One thousand hertz.", "system": "SI", "definition": "1 kHz = 1000 Hz", "usage": "Audio and radio", "transform": "linear", "factor": 1000 }, { "id": "mhz", "name": "Megahertz", "symbol": "MHz", "aliases": [ "megahertz" ], "description": "One million hertz.", "system": "SI", "definition": "1 MHz = 10⁶ Hz", "usage": "Radio and computing", "transform": "linear", "factor": 1000000 }, { "id": "ghz", "name": "Gigahertz", "symbol": "GHz", "aliases": [ "gigahertz" ], "description": "One billion hertz.", "system": "SI", "definition": "1 GHz = 10⁹ Hz", "usage": "Radio and computing", "transform": "linear", "factor": 1000000000 }, { "id": "thz", "name": "Terahertz", "symbol": "THz", "aliases": [ "terahertz" ], "description": "One trillion hertz.", "system": "SI", "definition": "1 THz = 10¹² Hz", "usage": "Optics and research", "transform": "linear", "factor": 1000000000000 }, { "id": "rpm", "name": "Revolutions per Minute", "symbol": "rpm", "aliases": [ "revolution per minute", "revolutions per minute" ], "description": "Rotational cycles per minute.", "system": "Mechanical", "definition": "60 rpm = 1 Hz", "usage": "Rotational speed", "transform": "linear", "factor": 0.016666666666666666 }, { "id": "bpm", "name": "Beats per Minute", "symbol": "BPM", "aliases": [ "bpm", "beat per minute", "beats per minute" ], "description": "Events or beats counted per minute.", "system": "Conventional", "definition": "60 BPM = 1 Hz", "usage": "Music tempo and event rates", "transform": "linear", "factor": 0.016666666666666666 }, { "id": "radps", "name": "Radians per Second", "symbol": "rad/s", "aliases": [ "radian per second", "radians per second", "rad/s" ], "description": "Angular frequency expressed in radians per second.", "system": "SI angular frequency", "definition": "2π rad/s = 1 Hz", "usage": "Angular frequency and engineering", "transform": "linear", "factor": 0.15915494309189535 } ] }, "angle": { "name": "Angle", "base": "rad", "dimension": "angle", "description": "Plane-angle units from astronomical sub-arcsecond scales through full rotations.", "units": [ { "id": "deg", "name": "Degree", "symbol": "°", "aliases": [ "degree", "degrees", "deg" ], "description": "One three-hundred-sixtieth of a full turn.", "system": "Conventional", "definition": "180° = π rad", "usage": "General angles", "transform": "linear", "factor": 0.017453292519943295 }, { "id": "rad", "name": "Radian", "symbol": "rad", "aliases": [ "radian", "radians" ], "description": "SI coherent angle unit.", "system": "SI", "definition": "1 rad = 1 rad", "usage": "Mathematics and physics", "transform": "linear", "factor": 1 }, { "id": "grad", "name": "Gradian", "symbol": "gon", "aliases": [ "gradian", "gradians", "grad", "gon" ], "description": "One four-hundredth of a full turn.", "system": "Surveying", "definition": "200 gon = π rad", "usage": "Surveying", "transform": "linear", "factor": 0.015707963267948967 }, { "id": "turn", "name": "Turn", "symbol": "turn", "aliases": [ "turns", "revolution", "revolutions", "rev" ], "description": "One complete rotation.", "system": "General", "definition": "1 turn = 2π rad = 360°", "usage": "Rotations", "transform": "linear", "factor": 6.283185307179586 }, { "id": "arcmin", "name": "Arcminute", "symbol": "′", "aliases": [ "arcminute", "arcminutes", "minute of arc", "minutes of arc" ], "description": "One sixtieth of a degree.", "system": "Angular", "definition": "60′ = 1°", "usage": "Astronomy and navigation", "transform": "linear", "factor": 0.0002908882086657216 }, { "id": "arcsec", "name": "Arcsecond", "symbol": "″", "aliases": [ "arcsecond", "arcseconds", "second of arc", "seconds of arc" ], "description": "One three-thousand-six-hundredth of a degree.", "system": "Angular", "definition": "3600″ = 1°", "usage": "Astronomy and navigation", "transform": "linear", "factor": 0.00000484813681109536 }, { "id": "mas", "name": "Milliarcsecond", "symbol": "mas", "aliases": [ "milliarcsecond", "milliarcseconds" ], "description": "One thousandth of an arcsecond.", "system": "Astronomical", "definition": "1 mas = 0.001 arcsec", "usage": "Precision astronomy and astrometry", "transform": "linear", "factor": 4.8481368110953594e-9 }, { "id": "quadrant", "name": "Quadrant", "symbol": "quadrant", "aliases": [ "quadrants" ], "description": "One quarter turn.", "system": "Conventional", "definition": "1 quadrant = 90° = π/2 rad", "usage": "Geometry and navigation", "transform": "linear", "factor": 1.5707963267948966 }, { "id": "sextant-angle", "name": "Sextant", "symbol": "sextant", "aliases": [ "sextants", "sextant angle" ], "description": "One sixth of a full turn.", "system": "Historical angular division", "definition": "1 sextant = 60° = π/3 rad", "usage": "Historical angular division", "transform": "linear", "factor": 1.0471975511965976 }, { "id": "octant", "name": "Octant", "symbol": "octant", "aliases": [ "octants" ], "description": "One eighth of a full turn.", "system": "Historical angular division", "definition": "1 octant = 45° = π/4 rad", "usage": "Geometry and navigation", "transform": "linear", "factor": 0.7853981633974483 }, { "id": "binary-degree", "name": "Binary Degree", "symbol": "brad", "aliases": [ "binary degree", "binary degrees", "binary radian", "binary radians" ], "description": "One two-hundred-fifty-sixth of a full turn.", "system": "Computing", "definition": "1 binary degree = 360°/256 = 1.40625°", "usage": "Digital angle representation", "transform": "linear", "factor": 0.02454369260617026 } ] }, "storage": { "name": "Data Storage", "base": "bit", "dimension": "storage", "description": "Decimal SI and binary IEC data storage units from individual bits through yotta-scale storage.", "units": [ { "id": "bit", "name": "Bit", "symbol": "bit", "aliases": [ "bits", "b" ], "description": "Binary digit.", "system": "Data", "definition": "1 bit = 1 bit", "usage": "Digital information", "transform": "linear", "factor": 1 }, { "id": "kbit", "name": "Kilobit", "symbol": "kbit", "aliases": [ "kilobit", "kilobits", "kb it" ], "description": "Decimal kilobit.", "system": "SI decimal", "definition": "1 kbit = 1000 bits", "usage": "Data size", "transform": "linear", "factor": 1000 }, { "id": "nibble", "name": "Nibble", "symbol": "nibble", "aliases": [ "nibbles", "half byte", "half-byte" ], "description": "Four-bit group equal to half a byte.", "system": "Data", "definition": "1 nibble = 4 bits", "usage": "Low-level computing and hexadecimal representation", "transform": "linear", "factor": 4 }, { "id": "mbit", "name": "Megabit", "symbol": "Mbit", "aliases": [ "megabit", "megabits" ], "description": "Decimal megabit.", "system": "SI decimal", "definition": "1 Mbit = 10⁶ bits", "usage": "Data size", "transform": "linear", "factor": 1000000 }, { "id": "gbit", "name": "Gigabit", "symbol": "Gbit", "aliases": [ "gigabit", "gigabits" ], "description": "Decimal gigabit.", "system": "SI decimal", "definition": "1 Gbit = 10⁹ bits", "usage": "Data size", "transform": "linear", "factor": 1000000000 }, { "id": "tbit", "name": "Terabit", "symbol": "Tbit", "aliases": [ "terabit", "terabits" ], "description": "Decimal terabit.", "system": "SI decimal", "definition": "1 Tbit = 10¹² bits", "usage": "Data size", "transform": "linear", "factor": 1000000000000 }, { "id": "pbit", "name": "Petabit", "symbol": "Pbit", "aliases": [ "petabit", "petabits" ], "description": "Decimal petabit.", "system": "SI decimal", "definition": "1 Pbit = 10¹⁵ bits", "usage": "Very large data sizes", "transform": "linear", "factor": 1000000000000000 }, { "id": "ebit", "name": "Exabit", "symbol": "Ebit", "aliases": [ "exabit", "exabits" ], "description": "Decimal exabit.", "system": "SI decimal", "definition": "1 Ebit = 10¹⁸ bits", "usage": "Exascale data", "transform": "linear", "factor": 1000000000000000000 }, { "id": "zbit", "name": "Zettabit", "symbol": "Zbit", "aliases": [ "zettabit", "zettabits" ], "description": "Decimal zettabit.", "system": "SI decimal", "definition": "1 Zbit = 10²¹ bits", "usage": "Global-scale data quantities", "transform": "linear", "factor": 1e+21 }, { "id": "ybit", "name": "Yottabit", "symbol": "Ybit", "aliases": [ "yottabit", "yottabits" ], "description": "Decimal yottabit.", "system": "SI decimal", "definition": "1 Ybit = 10²⁴ bits", "usage": "Extremely large data quantities", "transform": "linear", "factor": 1e+24 }, { "id": "byte", "name": "Byte", "symbol": "B", "aliases": [ "byte", "bytes" ], "description": "Eight bits.", "system": "Data", "definition": "1 byte = 8 bits", "usage": "Digital storage", "transform": "linear", "factor": 8 }, { "id": "kb", "name": "Kilobyte", "symbol": "KB", "aliases": [ "kb", "kilobyte", "kilobytes" ], "description": "Decimal kilobyte.", "system": "SI decimal", "definition": "1 KB = 1000 bytes", "usage": "Storage", "transform": "linear", "factor": 8000 }, { "id": "mb", "name": "Megabyte", "symbol": "MB", "aliases": [ "mb", "megabyte", "megabytes" ], "description": "Decimal megabyte.", "system": "SI decimal", "definition": "1 MB = 1000 KB", "usage": "Storage", "transform": "linear", "factor": 8000000 }, { "id": "gb", "name": "Gigabyte", "symbol": "GB", "aliases": [ "gb", "gigabyte", "gigabytes" ], "description": "Decimal gigabyte.", "system": "SI decimal", "definition": "1 GB = 1000 MB", "usage": "Storage", "transform": "linear", "factor": 8000000000 }, { "id": "tb", "name": "Terabyte", "symbol": "TB", "aliases": [ "tb", "terabyte", "terabytes" ], "description": "Decimal terabyte.", "system": "SI decimal", "definition": "1 TB = 1000 GB", "usage": "Storage", "transform": "linear", "factor": 8000000000000 }, { "id": "pb", "name": "Petabyte", "symbol": "PB", "aliases": [ "pb", "petabyte", "petabytes" ], "description": "Decimal petabyte.", "system": "SI decimal", "definition": "1 PB = 1000 TB", "usage": "Storage", "transform": "linear", "factor": 8000000000000000 }, { "id": "eb", "name": "Exabyte", "symbol": "EB", "aliases": [ "eb", "exabyte", "exabytes" ], "description": "Decimal exabyte.", "system": "SI decimal", "definition": "1 EB = 1000 PB = 10¹⁸ bytes", "usage": "Exascale storage", "transform": "linear", "factor": 8000000000000000000 }, { "id": "zb", "name": "Zettabyte", "symbol": "ZB", "aliases": [ "zb", "zettabyte", "zettabytes" ], "description": "Decimal zettabyte.", "system": "SI decimal", "definition": "1 ZB = 1000 EB = 10²¹ bytes", "usage": "Global data-scale storage", "transform": "linear", "factor": 8e+21 }, { "id": "yb", "name": "Yottabyte", "symbol": "YB", "aliases": [ "yb", "yottabyte", "yottabytes" ], "description": "Decimal yottabyte.", "system": "SI decimal", "definition": "1 YB = 1000 ZB = 10²⁴ bytes", "usage": "Extremely large storage quantities", "transform": "linear", "factor": 8e+24 }, { "id": "kib", "name": "Kibibyte", "symbol": "KiB", "aliases": [ "kibibyte", "kibibytes", "kib" ], "description": "Binary kibibyte.", "system": "IEC binary", "definition": "1 KiB = 1024 bytes", "usage": "Binary storage", "transform": "linear", "factor": 8192 }, { "id": "mib", "name": "Mebibyte", "symbol": "MiB", "aliases": [ "mebibyte", "mebibytes", "mib" ], "description": "Binary mebibyte.", "system": "IEC binary", "definition": "1 MiB = 1024 KiB", "usage": "Binary storage", "transform": "linear", "factor": 8388608 }, { "id": "gib", "name": "Gibibyte", "symbol": "GiB", "aliases": [ "gibibyte", "gibibytes", "gib" ], "description": "Binary gibibyte.", "system": "IEC binary", "definition": "1 GiB = 1024 MiB", "usage": "Binary storage", "transform": "linear", "factor": 8589934592 }, { "id": "tib", "name": "Tebibyte", "symbol": "TiB", "aliases": [ "tebibyte", "tebibytes", "tib" ], "description": "Binary tebibyte.", "system": "IEC binary", "definition": "1 TiB = 1024 GiB", "usage": "Binary storage", "transform": "linear", "factor": 8796093022208 }, { "id": "pib", "name": "Pebibyte", "symbol": "PiB", "aliases": [ "pebibyte", "pebibytes", "pib" ], "description": "Binary pebibyte.", "system": "IEC binary", "definition": "1 PiB = 1024 TiB", "usage": "Binary storage", "transform": "linear", "factor": 9007199254740992 }, { "id": "eib", "name": "Exbibyte", "symbol": "EiB", "aliases": [ "exbibyte", "exbibytes", "eib" ], "description": "Binary exbibyte.", "system": "IEC binary", "definition": "1 EiB = 1024 PiB = 2⁶⁰ bytes", "usage": "Exascale binary storage", "transform": "linear", "factor": 9223372036854776000 }, { "id": "zib", "name": "Zebibyte", "symbol": "ZiB", "aliases": [ "zebibyte", "zebibytes", "zib" ], "description": "Binary zebibyte.", "system": "IEC binary", "definition": "1 ZiB = 1024 EiB = 2⁷⁰ bytes", "usage": "Very large binary storage", "transform": "linear", "factor": 9.44473296573929e+21 }, { "id": "yib", "name": "Yobibyte", "symbol": "YiB", "aliases": [ "yobibyte", "yobibytes", "yib" ], "description": "Binary yobibyte.", "system": "IEC binary", "definition": "1 YiB = 1024 ZiB = 2⁸⁰ bytes", "usage": "Extremely large binary storage", "transform": "linear", "factor": 9.671406556917033e+24 } ] }, "data-rate": { "name": "Data Transfer Rate", "base": "bps", "dimension": "data-rate", "description": "Decimal SI and binary IEC bit/byte transfer rates per second.", "units": [ { "id": "bps", "name": "Bits per Second", "symbol": "bps", "aliases": [ "bit per second", "bits per second" ], "description": "One bit per second.", "system": "Data rate", "definition": "1 bps = 1 bit/s", "usage": "Network rate", "transform": "linear", "factor": 1 }, { "id": "kbps", "name": "Kilobits per Second", "symbol": "kbps", "aliases": [ "kilobit per second", "kilobits per second", "kbit/s" ], "description": "Decimal kilobits per second.", "system": "SI decimal", "definition": "1 kbps = 1000 bps", "usage": "Network rate", "transform": "linear", "factor": 1000 }, { "id": "mbps", "name": "Megabits per Second", "symbol": "Mbps", "aliases": [ "mbps", "megabit per second", "megabits per second", "mbit/s" ], "description": "Decimal megabits per second.", "system": "SI decimal", "definition": "1 Mbps = 10⁶ bps", "usage": "Internet speed", "transform": "linear", "factor": 1000000 }, { "id": "gbps", "name": "Gigabits per Second", "symbol": "Gbps", "aliases": [ "gbps", "gigabit per second", "gigabits per second", "gbit/s" ], "description": "Decimal gigabits per second.", "system": "SI decimal", "definition": "1 Gbps = 10⁹ bps", "usage": "High-speed networking", "transform": "linear", "factor": 1000000000 }, { "id": "tbps", "name": "Terabits per Second", "symbol": "Tbps", "aliases": [ "tbps", "terabit per second", "terabits per second" ], "description": "Decimal terabits per second.", "system": "SI decimal", "definition": "1 Tbps = 10¹² bps", "usage": "Backbone networking", "transform": "linear", "factor": 1000000000000 }, { "id": "Bps", "name": "Bytes per Second", "symbol": "B/s", "aliases": [ "byte per second", "bytes per second" ], "description": "Eight bits per second.", "system": "Data rate", "definition": "1 B/s = 8 bps", "usage": "Transfer rate", "transform": "linear", "factor": 8 }, { "id": "kBps", "name": "Kilobytes per Second", "symbol": "kB/s", "aliases": [ "kb/s", "kilobyte per second", "kilobytes per second" ], "description": "Decimal kilobytes per second.", "system": "SI decimal", "definition": "1 kB/s = 8000 bps", "usage": "Transfer rate", "transform": "linear", "factor": 8000 }, { "id": "MBps", "name": "Megabytes per Second", "symbol": "MB/s", "aliases": [ "mb/s", "megabyte per second", "megabytes per second" ], "description": "Decimal megabytes per second.", "system": "SI decimal", "definition": "1 MB/s = 8 Mbps", "usage": "Transfer rate", "transform": "linear", "factor": 8000000 }, { "id": "GBps", "name": "Gigabytes per Second", "symbol": "GB/s", "aliases": [ "gb/s", "gigabyte per second", "gigabytes per second" ], "description": "Decimal gigabytes per second.", "system": "SI decimal", "definition": "1 GB/s = 8 Gbps", "usage": "Transfer rate", "transform": "linear", "factor": 8000000000 }, { "id": "KiBps", "name": "Kibibytes per Second", "symbol": "KiB/s", "aliases": [ "kib/s", "kibibyte per second", "kibibytes per second" ], "description": "Binary kibibytes per second.", "system": "IEC binary", "definition": "1 KiB/s = 8192 bps", "usage": "Transfer rate", "transform": "linear", "factor": 8192 }, { "id": "MiBps", "name": "Mebibytes per Second", "symbol": "MiB/s", "aliases": [ "mib/s", "mebibyte per second", "mebibytes per second" ], "description": "Binary mebibytes per second.", "system": "IEC binary", "definition": "1 MiB/s = 8,388,608 bps", "usage": "Transfer rate", "transform": "linear", "factor": 8388608 }, { "id": "GiBps", "name": "Gibibytes per Second", "symbol": "GiB/s", "aliases": [ "gib/s", "gibibyte per second", "gibibytes per second" ], "description": "Binary gibibytes per second.", "system": "IEC binary", "definition": "1 GiB/s = 8,589,934,592 bps", "usage": "Transfer rate", "transform": "linear", "factor": 8589934592 }, { "id": "TBps", "name": "Terabytes per Second", "symbol": "TB/s", "aliases": [ "tb/s", "terabyte per second", "terabytes per second" ], "description": "Decimal terabytes per second.", "system": "SI decimal", "definition": "1 TB/s = 8×10¹² bps", "usage": "High-throughput storage and interconnects", "transform": "linear", "factor": 8000000000000 }, { "id": "PBps", "name": "Petabytes per Second", "symbol": "PB/s", "aliases": [ "pb/s", "petabyte per second", "petabytes per second" ], "description": "Decimal petabytes per second.", "system": "SI decimal", "definition": "1 PB/s = 8×10¹⁵ bps", "usage": "Extreme-scale data systems", "transform": "linear", "factor": 8000000000000000 }, { "id": "TiBps", "name": "Tebibytes per Second", "symbol": "TiB/s", "aliases": [ "tib/s", "tebibyte per second", "tebibytes per second" ], "description": "Binary tebibytes per second.", "system": "IEC binary", "definition": "1 TiB/s = 8,796,093,022,208 bps", "usage": "Binary high-throughput transfer rates", "transform": "linear", "factor": 8796093022208 }, { "id": "PiBps", "name": "Pebibytes per Second", "symbol": "PiB/s", "aliases": [ "pib/s", "pebibyte per second", "pebibytes per second" ], "description": "Binary pebibytes per second.", "system": "IEC binary", "definition": "1 PiB/s = 9,007,199,254,740,992 bps", "usage": "Binary extreme-scale transfer rates", "transform": "linear", "factor": 9007199254740992 } ] }, "fuel-economy": { "name": "Fuel Economy", "base": "kml", "dimension": "fuel-economy", "description": "Fuel efficiency including reciprocal liters-per-100-km units.", "units": [ { "id": "kml", "name": "Kilometers per Liter", "symbol": "km/L", "aliases": [ "km/l", "kilometer per liter", "kilometers per liter", "kilometre per litre", "kilometres per litre" ], "description": "Distance traveled per liter.", "system": "Metric", "definition": "1 km/L = 1 km/L", "usage": "Fuel economy", "transform": "linear", "factor": 1 }, { "id": "l100km", "name": "Liters per 100 Kilometers", "symbol": "L/100 km", "aliases": [ "l/100km", "l/100 km", "liters per 100 km", "litres per 100 km" ], "description": "Fuel consumption; lower is more efficient.", "system": "Metric", "definition": "km/L = 100 ÷ (L/100 km)", "usage": "Fuel consumption", "transform": "reciprocal", "reciprocal": 100 }, { "id": "mpg-us", "name": "US Miles per Gallon", "symbol": "US mpg", "aliases": [ "mpg", "us mpg", "mpg us", "miles per us gallon" ], "description": "Miles per US liquid gallon.", "system": "US customary", "definition": "1 US mpg ≈ 0.4251437075 km/L", "usage": "Vehicle fuel economy", "transform": "linear", "factor": 0.425143707430272 }, { "id": "mpg-imp", "name": "Imperial Miles per Gallon", "symbol": "Imp mpg", "aliases": [ "imperial mpg", "uk mpg", "mpg imperial", "miles per imperial gallon" ], "description": "Miles per imperial gallon.", "system": "Imperial", "definition": "1 Imp mpg ≈ 0.3540061899 km/L", "usage": "Vehicle fuel economy", "transform": "linear", "factor": 0.3540061899346471 } ] }, "cooking": { "name": "Cooking", "base": "ml", "dimension": "cooking-volume", "description": "International kitchen volume conversions with explicit US, metric, Australian and Imperial standards; ingredient mass requires density and is not guessed.", "units": [ { "id": "ml", "name": "Milliliter", "symbol": "mL", "aliases": [ "ml", "milliliter", "milliliters", "millilitre", "millilitres" ], "description": "Metric volume equal to one thousandth of a liter.", "system": "Metric", "definition": "1 mL = 0.001 L = 1 cm³", "usage": "Small liquid volumes and recipe measurements", "transform": "linear", "factor": 1 }, { "id": "cl", "name": "Centiliter", "symbol": "cL", "aliases": [ "cl", "centiliter", "centiliters", "centilitre", "centilitres" ], "description": "Metric volume equal to ten milliliters.", "system": "Metric", "definition": "1 cL = 10 mL", "usage": "Beverages and European recipes", "transform": "linear", "factor": 10 }, { "id": "dl", "name": "Deciliter", "symbol": "dL", "aliases": [ "dl", "deciliter", "deciliters", "decilitre", "decilitres" ], "description": "Metric volume equal to one hundred milliliters.", "system": "Metric", "definition": "1 dL = 100 mL", "usage": "European and Scandinavian recipes", "transform": "linear", "factor": 100 }, { "id": "l", "name": "Liter", "symbol": "L", "aliases": [ "l", "liter", "liters", "litre", "litres" ], "description": "Metric volume equal to one thousand milliliters.", "system": "Metric", "definition": "1 L = 1,000 mL", "usage": "Larger liquid volumes, beverages and recipe batches", "transform": "linear", "factor": 1000 }, { "id": "tsp", "name": "US Teaspoon", "symbol": "tsp", "aliases": [ "teaspoon", "teaspoons", "tsp", "us tsp", "us teaspoon", "us teaspoons" ], "description": "US customary cooking teaspoon derived from the US fluid ounce.", "system": "US customary", "definition": "1 US tsp = 4.92892159375 mL", "usage": "Small US recipe quantities, flavorings and seasonings", "transform": "linear", "factor": 4.92892159375 }, { "id": "tbsp", "name": "US Tablespoon", "symbol": "tbsp", "aliases": [ "tablespoon", "tablespoons", "tbsp", "us tbsp", "us tablespoon", "us tablespoons" ], "description": "US customary cooking tablespoon equal to three US teaspoons.", "system": "US customary", "definition": "1 US tbsp = 3 US tsp = 14.78676478125 mL", "usage": "US recipe liquids, oils and sauces", "transform": "linear", "factor": 14.78676478125 }, { "id": "cup", "name": "US Cup", "symbol": "cup", "aliases": [ "cup", "cups", "us cup", "us cups" ], "description": "US customary cup equal to eight US fluid ounces.", "system": "US customary", "definition": "1 US cup = 8 US fl oz = 236.5882365 mL", "usage": "US recipe volumes", "transform": "linear", "factor": 236.5882365 }, { "id": "fl-oz", "name": "US Fluid Ounce", "symbol": "fl oz", "aliases": [ "fluid ounce", "fluid ounces", "fl oz", "us fl oz", "us fluid ounce", "us fluid ounces" ], "description": "US customary liquid-volume fluid ounce.", "system": "US customary", "definition": "1 US fl oz = 29.5735295625 mL", "usage": "US beverage and recipe volumes", "transform": "linear", "factor": 29.5735295625 }, { "id": "pint", "name": "US Pint", "symbol": "pt", "aliases": [ "pint", "pints", "pt", "us pint", "us pints" ], "description": "US customary liquid pint equal to sixteen US fluid ounces.", "system": "US customary", "definition": "1 US pt = 16 US fl oz = 473.176473 mL", "usage": "US liquid ingredients and food-container volumes", "transform": "linear", "factor": 473.176473 }, { "id": "quart", "name": "US Quart", "symbol": "qt", "aliases": [ "quart", "quarts", "qt", "us quart", "us quarts" ], "description": "US customary liquid quart equal to two US pints.", "system": "US customary", "definition": "1 US qt = 2 US pt = 946.352946 mL", "usage": "US larger recipe batches and liquid-container volumes", "transform": "linear", "factor": 946.352946 }, { "id": "metric-tsp", "name": "Metric Teaspoon", "symbol": "metric tsp", "aliases": [ "metric teaspoon", "metric teaspoons", "5 ml teaspoon" ], "description": "Metric cooking teaspoon defined as five milliliters.", "system": "Metric cooking", "definition": "1 metric tsp = 5 mL", "usage": "Metric recipes and standardized measuring spoons", "transform": "linear", "factor": 5 }, { "id": "metric-tbsp", "name": "Metric Tablespoon", "symbol": "metric tbsp", "aliases": [ "metric tablespoon", "metric tablespoons", "15 ml tablespoon" ], "description": "Metric cooking tablespoon defined as fifteen milliliters.", "system": "Metric cooking", "definition": "1 metric tbsp = 15 mL", "usage": "Metric recipes outside the Australian 20 mL tablespoon convention", "transform": "linear", "factor": 15 }, { "id": "metric-dessertspoon", "name": "Metric Dessertspoon", "symbol": "dsp", "aliases": [ "dessertspoon", "dessertspoons", "metric dessertspoon", "metric dessertspoons", "10 ml spoon" ], "description": "Metric dessertspoon convention equal to ten milliliters.", "system": "Metric cooking", "definition": "1 metric dessertspoon = 10 mL", "usage": "Recipes using dessertspoon measures", "transform": "linear", "factor": 10 }, { "id": "metric-cup", "name": "Metric Cup", "symbol": "metric cup", "aliases": [ "metric cup", "metric cups", "250 ml cup" ], "description": "Metric cooking cup used in Australia, New Zealand and other metric recipe systems.", "system": "Metric cooking", "definition": "1 metric cup = 250 mL", "usage": "Metric and Commonwealth recipes", "transform": "linear", "factor": 250 }, { "id": "au-tbsp", "name": "Australian Tablespoon", "symbol": "AU tbsp", "aliases": [ "australian tablespoon", "australian tablespoons", "au tablespoon", "20 ml tablespoon" ], "description": "Australian standard cooking tablespoon equal to twenty milliliters.", "system": "Australian metric cooking", "definition": "1 Australian tbsp = 20 mL", "usage": "Australian recipes", "transform": "linear", "factor": 20 }, { "id": "imp-tsp", "name": "Imperial Teaspoon", "symbol": "Imp tsp", "aliases": [ "imperial teaspoon", "imperial teaspoons", "uk imperial teaspoon", "imp tsp" ], "description": "Historical Imperial cooking teaspoon equal to one third of an Imperial tablespoon.", "system": "Imperial", "definition": "1 Imp tsp = 5.919388020833333 mL", "usage": "Historical British and Imperial recipes", "transform": "linear", "factor": 5.919388020833333 }, { "id": "imp-tbsp", "name": "Imperial Tablespoon", "symbol": "Imp tbsp", "aliases": [ "imperial tablespoon", "imperial tablespoons", "uk imperial tablespoon", "imp tbsp" ], "description": "Historical Imperial tablespoon equal to three Imperial teaspoons.", "system": "Imperial", "definition": "1 Imp tbsp = 17.7581640625 mL", "usage": "Historical British and Imperial recipes", "transform": "linear", "factor": 17.7581640625 }, { "id": "imp-fl-oz", "name": "Imperial Fluid Ounce", "symbol": "Imp fl oz", "aliases": [ "imperial fluid ounce", "imperial fluid ounces", "uk fluid ounce", "uk fluid ounces", "imp fl oz" ], "description": "Imperial fluid ounce used in British Imperial liquid measure.", "system": "Imperial", "definition": "1 Imp fl oz = 28.4130625 mL", "usage": "British and Imperial liquid recipes", "transform": "linear", "factor": 28.4130625 }, { "id": "imp-pint", "name": "Imperial Pint", "symbol": "Imp pt", "aliases": [ "imperial pint", "imperial pints", "uk pint", "uk pints", "imp pint" ], "description": "Imperial liquid pint equal to twenty Imperial fluid ounces.", "system": "Imperial", "definition": "1 Imp pt = 568.26125 mL", "usage": "British and Imperial liquid measures", "transform": "linear", "factor": 568.26125 }, { "id": "imp-quart", "name": "Imperial Quart", "symbol": "Imp qt", "aliases": [ "imperial quart", "imperial quarts", "uk quart", "uk quarts", "imp quart" ], "description": "Imperial liquid quart equal to two Imperial pints.", "system": "Imperial", "definition": "1 Imp qt = 1,136.5225 mL", "usage": "British and Imperial larger liquid measures", "transform": "linear", "factor": 1136.5225 } ] }, "radioactivity": { "name": "Radioactive Activity", "base": "bq", "dimension": "radioactive activity", "description": "Radioactive decay activity measured as nuclear transitions per unit time.", "units": [ { "id": "bq", "name": "Becquerel", "symbol": "Bq", "aliases": [ "becquerel", "becquerels" ], "description": "SI unit of radioactive activity: one nuclear transition per second.", "system": "SI", "definition": "1 Bq = 1 s⁻¹", "usage": "Radioactive activity", "transform": "linear", "factor": 1 }, { "id": "kbq", "name": "Kilobecquerel", "symbol": "kBq", "aliases": [ "kilobecquerel", "kilobecquerels" ], "description": "One thousand becquerels.", "system": "SI", "definition": "1 kBq = 1,000 Bq", "usage": "Radioactive activity", "transform": "linear", "factor": 1000 }, { "id": "mBq", "name": "Millibecquerel", "symbol": "mBq", "aliases": [ "millibecquerel", "millibecquerels" ], "description": "One thousandth of a becquerel.", "system": "SI", "definition": "1 mBq = 0.001 Bq", "usage": "Low radioactive activity", "transform": "linear", "factor": 0.001 }, { "id": "MBq", "name": "Megabecquerel", "symbol": "MBq", "aliases": [ "megabecquerel", "megabecquerels" ], "description": "One million becquerels.", "system": "SI", "definition": "1 MBq = 1,000,000 Bq", "usage": "Radioactive activity", "transform": "linear", "factor": 1000000 }, { "id": "gbq", "name": "Gigabecquerel", "symbol": "GBq", "aliases": [ "gigabecquerel", "gigabecquerels" ], "description": "One billion becquerels.", "system": "SI", "definition": "1 GBq = 1,000,000,000 Bq", "usage": "Radioactive activity", "transform": "linear", "factor": 1000000000 }, { "id": "ci", "name": "Curie", "symbol": "Ci", "aliases": [ "curie", "curies" ], "description": "Non-SI unit of radioactive activity retained for radiological use.", "system": "Non-SI", "definition": "1 Ci = 3.7 × 10¹⁰ Bq", "usage": "Radioactive activity", "transform": "linear", "factor": 37000000000 }, { "id": "mci", "name": "Millicurie", "symbol": "mCi", "aliases": [ "millicurie", "millicuries" ], "description": "One thousandth of a curie.", "system": "Non-SI", "definition": "1 mCi = 3.7 × 10⁷ Bq", "usage": "Radioactive activity", "transform": "linear", "factor": 37000000 }, { "id": "uci", "name": "Microcurie", "symbol": "µCi", "aliases": [ "uCi", "uc", "microcurie", "microcuries", "μCi" ], "description": "One millionth of a curie.", "system": "Non-SI", "definition": "1 µCi = 3.7 × 10⁴ Bq", "usage": "Radioactive activity", "transform": "linear", "factor": 37000 }, { "id": "nci", "name": "Nanocurie", "symbol": "nCi", "aliases": [ "nanocurie", "nanocuries" ], "description": "One billionth of a curie.", "system": "Non-SI", "definition": "1 nCi = 37 Bq", "usage": "Radioactive activity", "transform": "linear", "factor": 37 }, { "id": "pci", "name": "Picocurie", "symbol": "pCi", "aliases": [ "picocurie", "picocuries" ], "description": "One trillionth of a curie.", "system": "Non-SI", "definition": "1 pCi = 0.037 Bq", "usage": "Radioactive activity", "transform": "linear", "factor": 0.037 }, { "id": "dpm", "name": "Disintegrations per minute", "symbol": "dpm", "aliases": [ "disintegration per minute", "disintegrations per minute", "decay per minute", "decays per minute" ], "description": "One radioactive transition per minute.", "system": "Rate", "definition": "1 dpm = 1/60 Bq", "usage": "Radioactive activity", "transform": "linear", "factor": 0.016666666666666666 } ] }, "radiation-dose": { "name": "Radiation Dose", "base": "sv", "dimension": "dose equivalent", "description": "Dose equivalent and effective-dose units expressed in sieverts and SI-prefixed sieverts.", "units": [ { "id": "sv", "name": "Sievert", "symbol": "Sv", "aliases": [ "sievert", "sieverts" ], "description": "SI derived unit used for dose equivalent and effective dose.", "system": "SI", "definition": "1 Sv = 1 J/kg for the defined dose quantities", "usage": "Radiation protection dose quantities", "transform": "linear", "factor": 1 }, { "id": "msv", "name": "Millisievert", "symbol": "mSv", "aliases": [ "millisievert", "millisieverts" ], "description": "One thousandth of a sievert.", "system": "SI", "definition": "1 mSv = 0.001 Sv", "usage": "Radiation protection dose quantities", "transform": "linear", "factor": 0.001 }, { "id": "usv", "name": "Microsievert", "symbol": "µSv", "aliases": [ "uSv", "μSv", "microsievert", "microsieverts" ], "description": "One millionth of a sievert.", "system": "SI", "definition": "1 µSv = 0.000001 Sv", "usage": "Radiation protection dose quantities", "transform": "linear", "factor": 0.000001 }, { "id": "nsv", "name": "Nanosievert", "symbol": "nSv", "aliases": [ "nanosievert", "nanosieverts" ], "description": "One billionth of a sievert.", "system": "SI", "definition": "1 nSv = 0.000000001 Sv", "usage": "Radiation protection dose quantities", "transform": "linear", "factor": 1e-9 } ] }, "time-duration": { "name": "Time Duration", "base": "s", "dimension": "time duration", "description": "Fixed-duration time units from femtoseconds through a defined Julian year.", "units": [ { "id": "ns", "name": "Nanosecond", "symbol": "ns", "aliases": [ "nanosecond", "nanoseconds" ], "description": "One billionth of a second.", "system": "SI", "definition": "1 ns = 10⁻⁹ s", "usage": "Computing and timing", "transform": "linear", "factor": 1e-9 }, { "id": "us", "name": "Microsecond", "symbol": "µs", "aliases": [ "us", "μs", "microsecond", "microseconds" ], "description": "One millionth of a second.", "system": "SI", "definition": "1 µs = 10⁻⁶ s", "usage": "Computing and electronics", "transform": "linear", "factor": 0.000001 }, { "id": "ms", "name": "Millisecond", "symbol": "ms", "aliases": [ "millisecond", "milliseconds" ], "description": "One thousandth of a second.", "system": "SI", "definition": "1 ms = 0.001 s", "usage": "Timing and latency", "transform": "linear", "factor": 0.001 }, { "id": "s", "name": "Second", "symbol": "s", "aliases": [ "sec", "secs", "second", "seconds" ], "description": "SI base unit of time.", "system": "SI", "definition": "1 s = 1 s", "usage": "General time duration", "transform": "linear", "factor": 1 }, { "id": "min", "name": "Minute", "symbol": "min", "aliases": [ "minute", "minutes", "mins" ], "description": "Sixty seconds.", "system": "Accepted with SI", "definition": "1 min = 60 s", "usage": "Everyday time", "transform": "linear", "factor": 60 }, { "id": "h", "name": "Hour", "symbol": "h", "aliases": [ "hr", "hrs", "hour", "hours" ], "description": "Sixty minutes.", "system": "Accepted with SI", "definition": "1 h = 3,600 s", "usage": "Everyday time", "transform": "linear", "factor": 3600 }, { "id": "d", "name": "Day", "symbol": "d", "aliases": [ "day", "days" ], "description": "Twenty-four hours.", "system": "Accepted with SI", "definition": "1 d = 86,400 s", "usage": "Fixed elapsed duration", "transform": "linear", "factor": 86400 }, { "id": "wk", "name": "Week", "symbol": "wk", "aliases": [ "week", "weeks", "wks" ], "description": "Seven fixed 24-hour days.", "system": "Conventional", "definition": "1 wk = 604,800 s", "usage": "Elapsed duration", "transform": "linear", "factor": 604800 }, { "id": "fortnight", "name": "Fortnight", "symbol": "fortnight", "aliases": [ "fortnights", "2 weeks", "two weeks" ], "description": "Fourteen fixed 24-hour days.", "system": "Conventional", "definition": "1 fortnight = 1,209,600 s", "usage": "Elapsed duration", "transform": "linear", "factor": 1209600 }, { "id": "ps", "name": "Picosecond", "symbol": "ps", "aliases": [ "picosecond", "picoseconds" ], "description": "One trillionth of a second.", "system": "SI", "definition": "1 ps = 10⁻¹² s", "usage": "Ultrafast electronics and timing", "transform": "linear", "factor": 1e-12 }, { "id": "fs", "name": "Femtosecond", "symbol": "fs", "aliases": [ "femtosecond", "femtoseconds" ], "description": "One quadrillionth of a second.", "system": "SI", "definition": "1 fs = 10⁻¹⁵ s", "usage": "Ultrafast optics and spectroscopy", "transform": "linear", "factor": 1e-15 }, { "id": "shake", "name": "Shake", "symbol": "shake", "aliases": [ "shakes" ], "description": "Informal nuclear-physics time unit equal to ten nanoseconds.", "system": "Scientific historical", "definition": "1 shake = 10⁻⁸ s", "usage": "Nuclear physics history", "transform": "linear", "factor": 1e-8 }, { "id": "julian-year", "name": "Julian Year", "symbol": "a", "aliases": [ "julian year", "julian years" ], "description": "Defined astronomical duration of exactly 365.25 days.", "system": "Astronomical", "definition": "1 Julian year = exactly 31,557,600 s", "usage": "Astronomy and light-year definitions", "transform": "linear", "factor": 31557600 } ] }, "electric-charge": { "name": "Electric Charge", "base": "coulomb", "dimension": "electric-charge", "description": "Electric charge units from SI coulombs to battery charge and elementary charge.", "units": [ { "id": "coulomb", "name": "Coulomb", "symbol": "C", "aliases": [ "coulomb", "coulombs" ], "description": "SI derived unit of electric charge.", "system": "SI", "definition": "1 C = 1 A·s", "usage": "Electrical science and engineering", "transform": "linear", "factor": 1 }, { "id": "mc", "name": "Millicoulomb", "symbol": "mC", "aliases": [ "millicoulomb", "millicoulombs" ], "description": "One thousandth of a coulomb.", "system": "SI", "definition": "1 mC = 0.001 C", "usage": "Electronics and instrumentation", "transform": "linear", "factor": 0.001 }, { "id": "uc", "name": "Microcoulomb", "symbol": "µC", "aliases": [ "uC", "μC", "microcoulomb", "microcoulombs" ], "description": "One millionth of a coulomb.", "system": "SI", "definition": "1 µC = 10⁻⁶ C", "usage": "Electrostatics and electronics", "transform": "linear", "factor": 0.000001 }, { "id": "nc", "name": "Nanocoulomb", "symbol": "nC", "aliases": [ "nanocoulomb", "nanocoulombs" ], "description": "One billionth of a coulomb.", "system": "SI", "definition": "1 nC = 10⁻⁹ C", "usage": "Small-signal charge measurement", "transform": "linear", "factor": 1e-9 }, { "id": "ah", "name": "Ampere-hour", "symbol": "Ah", "aliases": [ "ampere hour", "ampere-hour", "amp hours", "amp-hour" ], "description": "Charge transferred by one ampere flowing for one hour.", "system": "Accepted electrical", "definition": "1 Ah = 3600 C", "usage": "Battery capacity", "transform": "linear", "factor": 3600 }, { "id": "mah", "name": "Milliampere-hour", "symbol": "mAh", "aliases": [ "milliampere hour", "milliampere-hour", "milliamp hours" ], "description": "One thousandth of an ampere-hour.", "system": "Accepted electrical", "definition": "1 mAh = 3.6 C", "usage": "Consumer battery capacity", "transform": "linear", "factor": 3.6 }, { "id": "echarge", "name": "Elementary Charge", "symbol": "e", "aliases": [ "elementary charge", "electron charge magnitude" ], "description": "Exact SI-defined magnitude of the elementary electric charge.", "system": "SI defining constant", "definition": "1 e = 1.602176634×10⁻¹⁹ C", "usage": "Atomic and particle physics", "transform": "linear", "factor": 1.602176634e-19 }, { "id": "abc", "name": "Abcoulomb", "symbol": "abC", "aliases": [ "abcoulomb", "abcoulombs" ], "description": "CGS electromagnetic unit of charge.", "system": "CGS-EMU", "definition": "1 abC = 10 C", "usage": "Historical electromagnetic work", "transform": "linear", "factor": 10 } ] }, "electric-current": { "name": "Electric Current", "base": "ampere", "dimension": "electric-current", "description": "Electric current units from amperes through SI prefixes and CGS electromagnetic units.", "units": [ { "id": "ampere", "name": "Ampere", "symbol": "A", "aliases": [ "ampere", "amperes", "amp", "amps" ], "description": "SI base unit of electric current.", "system": "SI", "definition": "1 A = 1 C/s", "usage": "Electrical engineering", "transform": "linear", "factor": 1 }, { "id": "ma", "name": "Milliampere", "symbol": "mA", "aliases": [ "milliampere", "milliamperes", "milliamp", "milliamps" ], "description": "One thousandth of an ampere.", "system": "SI", "definition": "1 mA = 0.001 A", "usage": "Electronics", "transform": "linear", "factor": 0.001 }, { "id": "ua", "name": "Microampere", "symbol": "µA", "aliases": [ "uA", "μA", "microampere", "microamperes", "microamp", "microamps" ], "description": "One millionth of an ampere.", "system": "SI", "definition": "1 µA = 10⁻⁶ A", "usage": "Low-current electronics", "transform": "linear", "factor": 0.000001 }, { "id": "na", "name": "Nanoampere", "symbol": "nA", "aliases": [ "nanoampere", "nanoamperes" ], "description": "One billionth of an ampere.", "system": "SI", "definition": "1 nA = 10⁻⁹ A", "usage": "Sensors and semiconductor leakage", "transform": "linear", "factor": 1e-9 }, { "id": "ka", "name": "Kiloampere", "symbol": "kA", "aliases": [ "kiloampere", "kiloamperes" ], "description": "One thousand amperes.", "system": "SI", "definition": "1 kA = 1000 A", "usage": "Power systems and fault currents", "transform": "linear", "factor": 1000 }, { "id": "megaa", "name": "Megaampere", "symbol": "MA", "aliases": [ "megaampere", "megaamperes" ], "description": "One million amperes.", "system": "SI", "definition": "1 MA = 1,000,000 A", "usage": "High-current physics and pulsed power", "transform": "linear", "factor": 1000000 }, { "id": "aba", "name": "Abampere", "symbol": "abA", "aliases": [ "abampere", "abamperes", "biot" ], "description": "CGS electromagnetic current unit, also called the biot.", "system": "CGS-EMU", "definition": "1 abA = 10 A", "usage": "Historical electromagnetic work", "transform": "linear", "factor": 10 } ] }, "voltage": { "name": "Voltage", "base": "volt", "dimension": "electric-potential", "description": "Electric potential difference units using SI volt prefixes and legacy electromagnetic units.", "units": [ { "id": "volt", "name": "Volt", "symbol": "V", "aliases": [ "volt", "volts" ], "description": "SI derived unit of electric potential difference.", "system": "SI", "definition": "1 V = 1 J/C", "usage": "Electrical and electronic systems", "transform": "linear", "factor": 1 }, { "id": "mv", "name": "Millivolt", "symbol": "mV", "aliases": [ "millivolt", "millivolts" ], "description": "One thousandth of a volt.", "system": "SI", "definition": "1 mV = 0.001 V", "usage": "Sensors and electronics", "transform": "linear", "factor": 0.001 }, { "id": "uv", "name": "Microvolt", "symbol": "µV", "aliases": [ "uV", "μV", "microvolt", "microvolts" ], "description": "One millionth of a volt.", "system": "SI", "definition": "1 µV = 10⁻⁶ V", "usage": "Low-level instrumentation", "transform": "linear", "factor": 0.000001 }, { "id": "nv", "name": "Nanovolt", "symbol": "nV", "aliases": [ "nanovolt", "nanovolts" ], "description": "One billionth of a volt.", "system": "SI", "definition": "1 nV = 10⁻⁹ V", "usage": "Precision measurement", "transform": "linear", "factor": 1e-9 }, { "id": "kv", "name": "Kilovolt", "symbol": "kV", "aliases": [ "kilovolt", "kilovolts" ], "description": "One thousand volts.", "system": "SI", "definition": "1 kV = 1000 V", "usage": "Power distribution and high voltage", "transform": "linear", "factor": 1000 }, { "id": "megav", "name": "Megavolt", "symbol": "MV", "aliases": [ "megavolt", "megavolts" ], "description": "One million volts.", "system": "SI", "definition": "1 MV = 1,000,000 V", "usage": "High-voltage engineering", "transform": "linear", "factor": 1000000 }, { "id": "abv", "name": "Abvolt", "symbol": "abV", "aliases": [ "abvolt", "abvolts" ], "description": "CGS electromagnetic potential unit.", "system": "CGS-EMU", "definition": "1 abV = 10⁻⁸ V", "usage": "Historical electromagnetic work", "transform": "linear", "factor": 1e-8 } ] }, "resistance": { "name": "Electrical Resistance", "base": "ohm", "dimension": "electrical-resistance", "description": "Electrical resistance units from ohms through SI prefixes and the CGS abohm.", "units": [ { "id": "ohm", "name": "Ohm", "symbol": "Ω", "aliases": [ "ohm", "ohms" ], "description": "SI derived unit of electrical resistance.", "system": "SI", "definition": "1 Ω = 1 V/A", "usage": "Electrical and electronic circuits", "transform": "linear", "factor": 1 }, { "id": "mohm", "name": "Milliohm", "symbol": "mΩ", "aliases": [ "milliohm", "milliohms", "mohm" ], "description": "One thousandth of an ohm.", "system": "SI", "definition": "1 mΩ = 0.001 Ω", "usage": "Low-resistance measurements", "transform": "linear", "factor": 0.001 }, { "id": "uohm", "name": "Microohm", "symbol": "µΩ", "aliases": [ "uohm", "μΩ", "microohm", "microohms" ], "description": "One millionth of an ohm.", "system": "SI", "definition": "1 µΩ = 10⁻⁶ Ω", "usage": "Conductors, shunts and precision measurement", "transform": "linear", "factor": 0.000001 }, { "id": "kohm", "name": "Kilohm", "symbol": "kΩ", "aliases": [ "kohm", "kiloohm", "kiloohms" ], "description": "One thousand ohms.", "system": "SI", "definition": "1 kΩ = 1000 Ω", "usage": "Electronics", "transform": "linear", "factor": 1000 }, { "id": "megohm", "name": "Megohm", "symbol": "MΩ", "aliases": [ "megaohm", "megaohms", "megohm", "megohms" ], "description": "One million ohms.", "system": "SI", "definition": "1 MΩ = 1,000,000 Ω", "usage": "Insulation and electronics", "transform": "linear", "factor": 1000000 }, { "id": "gohm", "name": "Gigohm", "symbol": "GΩ", "aliases": [ "gigaohm", "gigaohms", "gohm" ], "description": "One billion ohms.", "system": "SI", "definition": "1 GΩ = 10⁹ Ω", "usage": "High-impedance instrumentation", "transform": "linear", "factor": 1000000000 }, { "id": "abohm", "name": "Abohm", "symbol": "abΩ", "aliases": [ "abohm", "abohms" ], "description": "CGS electromagnetic resistance unit.", "system": "CGS-EMU", "definition": "1 abΩ = 10⁻⁹ Ω", "usage": "Historical electromagnetic work", "transform": "linear", "factor": 1e-9 } ] }, "capacitance": { "name": "Capacitance", "base": "farad", "dimension": "capacitance", "description": "Capacitance units from farads to common SI submultiples used in electronics.", "units": [ { "id": "farad", "name": "Farad", "symbol": "F", "aliases": [ "farad", "farads" ], "description": "SI derived unit of capacitance.", "system": "SI", "definition": "1 F = 1 C/V", "usage": "Electrical engineering", "transform": "linear", "factor": 1 }, { "id": "mf", "name": "Millifarad", "symbol": "mF", "aliases": [ "millifarad", "millifarads" ], "description": "One thousandth of a farad.", "system": "SI", "definition": "1 mF = 10⁻³ F", "usage": "Large capacitors and power electronics", "transform": "linear", "factor": 0.001 }, { "id": "uf", "name": "Microfarad", "symbol": "µF", "aliases": [ "uF", "μF", "microfarad", "microfarads" ], "description": "One millionth of a farad.", "system": "SI", "definition": "1 µF = 10⁻⁶ F", "usage": "General electronics", "transform": "linear", "factor": 0.000001 }, { "id": "nf", "name": "Nanofarad", "symbol": "nF", "aliases": [ "nanofarad", "nanofarads" ], "description": "One billionth of a farad.", "system": "SI", "definition": "1 nF = 10⁻⁹ F", "usage": "Electronics and filters", "transform": "linear", "factor": 1e-9 }, { "id": "pf", "name": "Picofarad", "symbol": "pF", "aliases": [ "picofarad", "picofarads" ], "description": "One trillionth of a farad.", "system": "SI", "definition": "1 pF = 10⁻¹² F", "usage": "RF and small capacitors", "transform": "linear", "factor": 1e-12 }, { "id": "ff", "name": "Femtofarad", "symbol": "fF", "aliases": [ "femtofarad", "femtofarads" ], "description": "10⁻¹⁵ farad.", "system": "SI", "definition": "1 fF = 10⁻¹⁵ F", "usage": "Integrated circuits and device physics", "transform": "linear", "factor": 1e-15 }, { "id": "af", "name": "Attofarad", "symbol": "aF", "aliases": [ "attofarad", "attofarads" ], "description": "10⁻¹⁸ farad.", "system": "SI", "definition": "1 aF = 10⁻¹⁸ F", "usage": "Nanoscale capacitance", "transform": "linear", "factor": 1e-18 } ] }, "inductance": { "name": "Inductance", "base": "henry", "dimension": "inductance", "description": "Inductance units from henries to common SI submultiples used in electronics and power systems.", "units": [ { "id": "henry", "name": "Henry", "symbol": "H", "aliases": [ "henry", "henries" ], "description": "SI derived unit of inductance.", "system": "SI", "definition": "1 H = 1 Wb/A", "usage": "Electrical engineering", "transform": "linear", "factor": 1 }, { "id": "mh", "name": "Millihenry", "symbol": "mH", "aliases": [ "millihenry", "millihenries" ], "description": "One thousandth of a henry.", "system": "SI", "definition": "1 mH = 10⁻³ H", "usage": "Inductors and filters", "transform": "linear", "factor": 0.001 }, { "id": "uh", "name": "Microhenry", "symbol": "µH", "aliases": [ "uH", "μH", "microhenry", "microhenries" ], "description": "One millionth of a henry.", "system": "SI", "definition": "1 µH = 10⁻⁶ H", "usage": "RF and switch-mode electronics", "transform": "linear", "factor": 0.000001 }, { "id": "nh", "name": "Nanohenry", "symbol": "nH", "aliases": [ "nanohenry", "nanohenries" ], "description": "One billionth of a henry.", "system": "SI", "definition": "1 nH = 10⁻⁹ H", "usage": "RF circuits and parasitic inductance", "transform": "linear", "factor": 1e-9 }, { "id": "ph", "name": "Picohenry", "symbol": "pH", "aliases": [ "picohenry", "picohenries" ], "description": "One trillionth of a henry.", "system": "SI", "definition": "1 pH = 10⁻¹² H", "usage": "Microwave and nanoscale circuits", "transform": "linear", "factor": 1e-12 }, { "id": "fh", "name": "Femtohenry", "symbol": "fH", "aliases": [ "femtohenry", "femtohenries" ], "description": "10⁻¹⁵ henry.", "system": "SI", "definition": "1 fH = 10⁻¹⁵ H", "usage": "Device-scale inductance", "transform": "linear", "factor": 1e-15 }, { "id": "kh", "name": "Kilohenry", "symbol": "kH", "aliases": [ "kilohenry", "kilohenries" ], "description": "One thousand henries.", "system": "SI", "definition": "1 kH = 1000 H", "usage": "Very large inductance references", "transform": "linear", "factor": 1000 } ] }, "volume-flow": { "name": "Volumetric Flow Rate", "base": "m3s", "dimension": "volume-flow-rate", "description": "Volumetric flow rate units for fluids and ventilation. Mass flow is a separate quantity and requires density to relate to volume flow.", "units": [ { "id": "m3s", "name": "Cubic Meter per Second", "symbol": "m³/s", "aliases": [ "m3/s", "cubic meter per second", "cubic meters per second", "cubic metre per second", "cubic metres per second" ], "description": "SI volumetric flow rate unit.", "system": "SI", "definition": "1 m³/s = 1 m³/s", "usage": "Hydraulics and process engineering", "transform": "linear", "factor": 1 }, { "id": "m3h", "name": "Cubic Meter per Hour", "symbol": "m³/h", "aliases": [ "m3/h", "cubic meter per hour", "cubic meters per hour", "cubic metre per hour", "cubic metres per hour" ], "description": "Cubic meters passing per hour.", "system": "Metric", "definition": "1 m³/h = 1/3600 m³/s", "usage": "HVAC and process flow", "transform": "linear", "factor": 0.0002777777777777778 }, { "id": "ls", "name": "Liter per Second", "symbol": "L/s", "aliases": [ "l/s", "liter per second", "liters per second", "litre per second", "litres per second" ], "description": "Liters passing per second.", "system": "Metric", "definition": "1 L/s = 0.001 m³/s", "usage": "Water and ventilation", "transform": "linear", "factor": 0.001 }, { "id": "lmin", "name": "Liter per Minute", "symbol": "L/min", "aliases": [ "l/min", "liter per minute", "liters per minute", "litre per minute", "litres per minute" ], "description": "Liters passing per minute.", "system": "Metric", "definition": "1 L/min = 1/60000 m³/s", "usage": "Pumps, plumbing and medical equipment", "transform": "linear", "factor": 0.000016666666666666667 }, { "id": "mls", "name": "Milliliter per Second", "symbol": "mL/s", "aliases": [ "ml/s", "milliliter per second", "milliliters per second", "millilitre per second", "millilitres per second" ], "description": "Milliliters passing per second.", "system": "Metric", "definition": "1 mL/s = 10⁻⁶ m³/s", "usage": "Laboratory and small-flow systems", "transform": "linear", "factor": 0.000001 }, { "id": "gpm-us", "name": "US Gallon per Minute", "symbol": "US gpm", "aliases": [ "gpm", "us gpm", "gallon per minute", "gallons per minute", "us gallon per minute", "us gallons per minute" ], "description": "US liquid gallons passing per minute.", "system": "US customary", "definition": "1 US gpm = 0.0000630901964 m³/s", "usage": "Pumps, plumbing and water systems", "transform": "linear", "factor": 0.0000630901964 }, { "id": "cfm", "name": "Cubic Foot per Minute", "symbol": "CFM", "aliases": [ "cfm", "ft3/min", "cubic foot per minute", "cubic feet per minute" ], "description": "Cubic feet passing per minute.", "system": "Imperial/US customary", "definition": "1 CFM = 0.0004719474432 m³/s", "usage": "Ventilation and air handling", "transform": "linear", "factor": 0.0004719474432 }, { "id": "bpd", "name": "Oil Barrel per Day", "symbol": "bbl/d", "aliases": [ "bbl/day", "barrel per day", "barrels per day", "oil barrel per day", "oil barrels per day" ], "description": "Petroleum barrels flowing per day using the 42-US-gallon oil barrel.", "system": "Petroleum industry", "definition": "1 bbl/d = 0.158987294928 m³/day", "usage": "Oil production and transport", "transform": "linear", "factor": 0.0000018401307283333333 } ] }, "dynamic-viscosity": { "name": "Dynamic Viscosity", "base": "pas", "dimension": "dynamic-viscosity", "description": "Dynamic viscosity units for fluid resistance to shear. Kinematic viscosity is kept separate because relating the two requires density.", "units": [ { "id": "pas", "name": "Pascal-second", "symbol": "Pa·s", "aliases": [ "pa s", "pa·s", "pascal second", "pascal-second", "pascal seconds" ], "description": "SI unit of dynamic viscosity.", "system": "SI", "definition": "1 Pa·s = 1 kg/(m·s)", "usage": "Fluid mechanics and rheology", "transform": "linear", "factor": 1 }, { "id": "mpas", "name": "Millipascal-second", "symbol": "mPa·s", "aliases": [ "mpa s", "mpa·s", "millipascal second", "millipascal-second", "millipascal seconds" ], "description": "One thousandth of a pascal-second.", "system": "SI", "definition": "1 mPa·s = 0.001 Pa·s", "usage": "Liquid viscosity", "transform": "linear", "factor": 0.001 }, { "id": "poise", "name": "Poise", "symbol": "P", "aliases": [ "poise", "poises" ], "description": "CGS dynamic viscosity unit.", "system": "CGS", "definition": "1 P = 0.1 Pa·s", "usage": "Rheology and legacy fluid data", "transform": "linear", "factor": 0.1 }, { "id": "cp", "name": "Centipoise", "symbol": "cP", "aliases": [ "centipoise", "centipoises" ], "description": "One hundredth of a poise, numerically equal to one mPa·s.", "system": "CGS", "definition": "1 cP = 0.001 Pa·s", "usage": "Common liquid-viscosity data", "transform": "linear", "factor": 0.001 }, { "id": "up", "name": "Micropoise", "symbol": "µP", "aliases": [ "uP", "μP", "micropoise", "micropoises" ], "description": "One millionth of a poise.", "system": "CGS", "definition": "1 µP = 10⁻⁷ Pa·s", "usage": "Very low dynamic viscosity", "transform": "linear", "factor": 1e-7 } ] }, "kinematic-viscosity": { "name": "Kinematic Viscosity", "base": "m2s", "dimension": "kinematic-viscosity", "description": "Kinematic viscosity units for momentum diffusivity. Dynamic viscosity is kept separate because converting between them requires fluid density.", "units": [ { "id": "m2s", "name": "Square Meter per Second", "symbol": "m²/s", "aliases": [ "m2/s", "square meter per second", "square meters per second", "square metre per second", "square metres per second" ], "description": "SI unit of kinematic viscosity.", "system": "SI", "definition": "1 m²/s = 1 m²/s", "usage": "Fluid mechanics", "transform": "linear", "factor": 1 }, { "id": "mm2s", "name": "Square Millimeter per Second", "symbol": "mm²/s", "aliases": [ "mm2/s", "square millimeter per second", "square millimeters per second", "square millimetre per second", "square millimetres per second" ], "description": "One millionth of a square meter per second.", "system": "SI", "definition": "1 mm²/s = 10⁻⁶ m²/s", "usage": "Lubricant specifications", "transform": "linear", "factor": 0.000001 }, { "id": "cm2s", "name": "Square Centimeter per Second", "symbol": "cm²/s", "aliases": [ "cm2/s", "square centimeter per second", "square centimeters per second", "square centimetre per second", "square centimetres per second" ], "description": "One ten-thousandth of a square meter per second.", "system": "CGS/metric", "definition": "1 cm²/s = 10⁻⁴ m²/s", "usage": "Fluid-property data", "transform": "linear", "factor": 0.0001 }, { "id": "st", "name": "Stokes", "symbol": "St", "aliases": [ "stokes" ], "description": "CGS unit of kinematic viscosity.", "system": "CGS", "definition": "1 St = 1 cm²/s = 10⁻⁴ m²/s", "usage": "Legacy fluid-property data", "transform": "linear", "factor": 0.0001 }, { "id": "cst", "name": "Centistokes", "symbol": "cSt", "aliases": [ "centistokes", "centistoke" ], "description": "One hundredth of a stokes, numerically equal to one mm²/s.", "system": "CGS", "definition": "1 cSt = 10⁻⁶ m²/s", "usage": "Lubricants and petroleum products", "transform": "linear", "factor": 0.000001 }, { "id": "ft2s", "name": "Square Foot per Second", "symbol": "ft²/s", "aliases": [ "ft2/s", "square foot per second", "square feet per second" ], "description": "Kinematic viscosity in square feet per second.", "system": "Imperial/US customary", "definition": "1 ft²/s = 0.09290304 m²/s", "usage": "Engineering data", "transform": "linear", "factor": 0.09290304 } ] }, "illuminance": { "name": "Illuminance", "base": "lux", "dimension": "illuminance", "description": "Illuminance units measuring luminous flux incident on a surface. Lumen and candela are different photometric quantities and are not directly converted here.", "units": [ { "id": "lux", "name": "Lux", "symbol": "lx", "aliases": [ "lux", "luxes" ], "description": "SI derived unit of illuminance.", "system": "SI", "definition": "1 lx = 1 lm/m²", "usage": "Lighting design and measurement", "transform": "linear", "factor": 1 }, { "id": "klux", "name": "Kilolux", "symbol": "klx", "aliases": [ "kilolux" ], "description": "One thousand lux.", "system": "SI", "definition": "1 klx = 1000 lx", "usage": "Bright daylight and high illuminance", "transform": "linear", "factor": 1000 }, { "id": "fc", "name": "Foot-candle", "symbol": "fc", "aliases": [ "foot candle", "foot-candle", "foot candles", "foot-candles" ], "description": "Illuminance of one lumen per square foot.", "system": "US customary lighting", "definition": "1 fc = 10.7639104167097 lx", "usage": "Architectural and workplace lighting", "transform": "linear", "factor": 10.763910416709722 }, { "id": "phot", "name": "Phot", "symbol": "ph", "aliases": [ "phot", "phots" ], "description": "CGS illuminance unit.", "system": "CGS", "definition": "1 ph = 10,000 lx", "usage": "Historical photometry", "transform": "linear", "factor": 10000 } ] }, "luminance": { "name": "Luminance", "base": "nit", "dimension": "luminance", "description": "Luminance units describing luminous intensity per projected area. Illuminance, luminous flux and luminous intensity are separate quantities.", "units": [ { "id": "nit", "name": "Nit", "symbol": "nt", "aliases": [ "nit", "nits", "cd/m2", "cd/m²", "candela per square meter", "candelas per square meter", "candela per square metre", "candelas per square metre" ], "description": "Common name for one candela per square meter.", "system": "SI-derived photometry", "definition": "1 nt = 1 cd/m²", "usage": "Displays and lighting", "transform": "linear", "factor": 1 }, { "id": "fL", "name": "Foot-lambert", "symbol": "fL", "aliases": [ "foot lambert", "foot-lambert", "foot lamberts", "foot-lamberts" ], "description": "Luminance unit historically used for projection screens.", "system": "US customary photometry", "definition": "1 fL ≈ 3.4262590996 cd/m²", "usage": "Cinema and projection", "transform": "linear", "factor": 3.4262590996353905 }, { "id": "stilb", "name": "Stilb", "symbol": "sb", "aliases": [ "stilb", "stilbs" ], "description": "CGS luminance unit equal to one candela per square centimeter.", "system": "CGS", "definition": "1 sb = 10,000 cd/m²", "usage": "Historical photometry", "transform": "linear", "factor": 10000 }, { "id": "lambert", "name": "Lambert", "symbol": "L", "aliases": [ "lambert", "lamberts" ], "description": "CGS luminance unit based on a perfectly diffusing surface.", "system": "CGS", "definition": "1 L = 10,000/π cd/m²", "usage": "Historical photometry", "transform": "linear", "factor": 3183.098861837907 }, { "id": "apostilb", "name": "Apostilb", "symbol": "asb", "aliases": [ "apostilb", "apostilbs" ], "description": "Luminance unit equal to one lumen per square meter divided by π steradians.", "system": "Legacy photometry", "definition": "1 asb = 1/π cd/m²", "usage": "Historical photometry", "transform": "linear", "factor": 0.3183098861837907 } ] } } }