units-convert

This tool is modified from convert-units, adding the following functions:

• Solve the problem of floating-point precision after unit conversion
• More types of units
• Add 中文文档

A handy utility for converting between quantities in different units.

Installation

npm install units-convert --save

Usage

units-convert has a simple chained API that is easy to read.

Here's how you move between the metric units for volume:

var convert = require('units-convert')

convert(1).from('l').to('ml')
// 1000

Jump from imperial to metric units the same way:

convert(1).from('lb').to('kg')
// 0.4536... (tested to 4 significant figures)

Just be careful not to ask for an impossible conversion:

convert(1).from('oz').to('fl-oz')
// throws -- you can't go from mass to volume!

You can ask units-convert to select the best unit for you. You can also optionally explicitly exclude orders of magnitude or specify a cut off number for selecting the best representation.

convert(12000).from('mm').toBest()
// 12 Meters (the smallest unit with a value above 1)

convert(12000).from('mm').toBest({ exclude: ['m'] })
// 1200 Centimeters (the smallest unit excluding meters)

convert(900).from('mm').toBest({ cutOffNumber: 10 });
// 900 Centimeters (the smallest unit with a value equal to or above 10)

convert(1000).from('mm').toBest({ cutOffNumber: 10 })
// 10 Meters (the smallest unit with a value equal to or above 10)

You can get a list of the measurement types supported with .measures

convert().measures()
// [ 'length', 'mass', 'volume' ]

If you ever want to know the possible conversions for a unit, just use .possibilities

convert().from('l').possibilities()
// [ 'ml', 'l', 'tsp', 'Tbs', 'fl-oz', 'cup', 'pnt', 'qt', 'gal' ]

convert().from('kg').possibilities()
// [ 'mcg', 'mg', 'g', 'kg', 'oz', 'lb' ]

You can also get the possible conversions for a measure:

convert().possibilities('mass')
// [ 'mcg', 'mg', 'g', 'kg', 'oz', 'lb', 'mt', 't' ]

You can also get the all the available units:

convert().possibilities()
// [ 'mm', 'cm', 'm', 'in', 'ft-us', 'ft', 'mi', 'mcg', 'mg', 'g', 'kg', 'oz', 'lb', 'mt', 't', 'ml', 'l', 'tsp', 'Tbs', 'fl-oz', 'cup', 'pnt', 'qt', 'gal', 'ea', 'dz' ];

To get a detailed description of a unit, use describe

convert().describe('kg')
/*
  {
    abbr: 'kg',
    measure: 'mass',
    system: 'metric',
    singular: 'Kilogram',
    plural: 'Kilograms',
  }
*/

To get detailed descriptions of all units, use list.

convert().list()
/*
  [{
    abbr: 'kg',
    measure: 'mass',
    system: 'metric',
    singular: 'Kilogram',
    plural: 'Kilograms',
  }, ...]
*/

You can also get detailed descriptions of all units for a measure:

convert().list('mass')
/*
  [{
    abbr: 'kg',
    measure: 'mass',
    system: 'metric',
    singular: 'Kilogram',
    plural: 'Kilograms',
  }, ...]
*/

Supported Units

Length

• nm: nanometer
• μm: micrometer
• mm: millimeter
• cm: centimeter
• m: meter
• km: kilometer
• in: inch
• yd: yard
• ft-us: U.S. survey foot
• ft: foot
• fathom: fathom
• mi: mile
• nMi: nautical mile

Area

• mm2: square millimeter
• cm2: square centimeter
• m2: square meter
• ha: hectare
• km2: square kilometer
• in2: square inch
• ft2: square foot
• ac: acre
• mi2: square mile

Mass

• mcg: microgram
• mg: milligram
• g: gram
• kg: kilogram
• oz: ounce
• lb: pound
• mt: metric ton
• t: ton

Volume

• mm3: cubic millimeter
• cm3: cubic centimeter
• ml: milliliter
• l: liter
• kl: kiloliter
• Ml: megaliter
• Gl: gigaliter
• m3: cubic meter
• km3: cubic kilometer
• tsp: teaspoon
• Tbs: tablespoon
• in3: cubic inch
• fl-oz: fluid ounce
• cup: cup
• pnt: pint
• qt: quart
• gal: gallon
• ft3: cubic foot
• yd3: cubic yard

Volume Flow Rate

• mm3/s: cubic millimeter per second
• cm3/s: cubic centimeter per second
• ml/s: milliliter per second
• cl/s: centiliter per second
• dl/s: deciliter per second
• l/s: liter per second
• l/min: liter per minute
• l/h: liter per hour
• kl/s: kiloliter per second
• kl/min: kiloliter per minute
• kl/h: kiloliter per hour
• m3/s: cubic meter per second
• m3/min: cubic meter per minute
• m3/h: cubic meter per hour
• km3/s: cubic kilometer per second
• tsp/s: teaspoon per second
• Tbs/s: tablespoon per second
• in3/s: cubic inch per second
• in3/min: cubic inch per minute
• in3/h: cubic inch per hour
• fl-oz/s: fluid ounce per second
• fl-oz/min: fluid ounce per minute
• fl-oz/h: fluid ounce per hour
• cup/s: cup per second
• pnt/s: pint per second
• pnt/min: pint per minute
• pnt/h: pint per hour
• qt/s: quart per second
• gal/s: gallon per second
• gal/min: gallon per minute
• gal/h: gallon per hour
• ft3/s: cubic foot per second
• ft3/min: cubic foot per minute
• ft3/h: cubic foot per hour
• yd3/s: cubic yard per second
• yd3/min: cubic yard per minute
• yd3/h: cubic yard per hour

Temperature

• C: Celsius
• F: Fahrenheit
• K: Kelvin
• R: Rankine

Time

• ns: nanosecond
• μs: microsecond
• ms: millisecond
• s: second
• min: minute
• h: hour
• d: day
• week: week
• month: month
• year: year

Frequency

• Hz: hertz
• mHz: millihertz
• kHz: kilohertz
• MHz: megahertz
• GHz: gigahertz
• THz: terahertz
• rpm: revolutions per minute
• deg/s: degrees per second
• rad/s: radians per second

Speed

• m/s: meters per second
• km/h: kilometers per hour
• mph: miles per hour
• knot: knots
• ft/s: feet per second
• in/h: inches per hour
• mm/h: millimeters per hour

Pace

• s/m: seconds per meter
• min/km: minutes per kilometer
• s/ft: seconds per foot
• min/mi: minutes per mile

Pressure

• Pa: Pascal
• hPa: hectopascal
• kPa: kilopascal
• MPa: megapascal
• bar: bar
• torr: torr
• mH2O: meter of water column
• mmHg: millimeters of mercury
• psi: pound per square inch
• ksi: kilo pound per square inch

Digital

• b: bit
• Kb: kilobit
• Mb: megabit
• Gb: gigabit
• Tb: terabit
• B: byte
• KB: kilobyte
• MB: megabyte
• GB: gigabyte
• TB: terabyte

Illuminance

• lx: lux
• ft-cd: foot-candle

Parts-Per

• ppm: parts per million
• ppb: parts per billion
• ppt: parts per trillion
• ppq: parts per quadrillion

Voltage

• V: Volt
• mV: millivolt
• kV: kilovolt

Current

• A: Ampere
• mA: milliampere
• kA: kiloampere

Power

• W: Watt
• mW: milliwatt
• kW: kilowatt
• MW: megawatt
• GW: gigawatt
• PS: petawatt
• Btu/s: British thermal unit per second
• ft-lb/s: foot-pound per second
• hp: horsepower

Apparent Power

• VA: volt-ampere
• mVA: millivolt-ampere
• kVA: kilovolt-ampere
• MVA: megavolt-ampere
• GVA: gigavolt-ampere

Reactive Power

• VAR: volt-ampere reactive
• mVAR: millivolt-ampere reactive
• kVAR: kilovolt-ampere reactive
• MVAR: megavolt-ampere reactive
• GVAR: gigavolt-ampere reactive

Energy

• Ws: watt-second
• Wh: watt-hour
• mWh: milliwatt-hour
• kWh: kilowatt-hour
• MWh: megawatt-hour
• GWh: gigawatt-hour
• J: joule
• kJ: kilojoule
• MJ: megajoule
• GJ: gigajoule

Reactive Energy

• VARh: volt-ampere reactive hour
• mVARh: millivolt-ampere reactive hour
• kVARh: kilovolt-ampere reactive hour
• MVARh: megavolt-ampere reactive hour
• GVARh: gigavolt-ampere reactive hour

Angle

• deg: degree
• rad: radian
• grad: gradian
• arcmin: arcminute
• arcsec: arcsecond

Charge

• c: coulomb
• mC: milliampere
• μC: microcoulomb
• nC: nanocoulomb
• pC: picocoulomb

Force

• N: Newton
• kN: kilonewton
• lbf: pound-force

Acceleration

• g (g-force): acceleration due to gravity
• m/s2: standard acceleration

Pieces

• pcs: pieces
• bk-doz: baker's dozen
• cp: cents
• doz-doz: dozen dozen
• doz: dozen
• gr-gr: gross gross
• gros: gross
• half-dozen: half a dozen
• long-hundred: long hundred
• ream: ream
• scores: scores
• sm-gr: small gross
• trio: trio