Units

Nineteen categories of measurement. Every pair of units has its own page with the formula and tables in both directions.

mm · cm · m · km · mil · in · ft · yd · mi · M

Metres ↔ feet Inches ↔ centimetres Kilometres ↔ miles

mg · g · dag · hg · kg · t · oz · lb · st

Kilograms ↔ pounds Grams ↔ ounces Stone ↔ kilograms

ml · cl · dl · l · m³ · tsp · tbsp · cup · fl oz · fl oz (UK) · pt · pt (UK) · gal · gal (UK)

Millilitres ↔ US cups Litres ↔ US gallons Millilitres ↔ tablespoons

°C · °F · K

Degrees Celsius ↔ degrees Fahrenheit Degrees Celsius ↔ kelvin

m/s · km/h · mph · kn · ft/s

Kilometres per hour ↔ miles per hour Metres per second ↔ kilometres per hour Knots ↔ kilometres per hour

Pa · hPa · kPa · bar · atm · psi · mmHg

Bar ↔ psi Kilopascals ↔ bar Atmospheres ↔ bar

mm² · cm² · m² · ha · km² · ft² · ac · mi²

Square metres ↔ square feet Hectares ↔ acres

J · kJ · MJ · cal · kcal · Wh · kWh · MWh · BTU · ft·lb · eV

Kilocalories ↔ kilojoules Kilowatt-hours ↔ megajoules British thermal units ↔ kilowatt-hours

W · kW · MW · hp · PS · BTU/h

Kilowatts ↔ horsepower (mechanical) Horsepower (mechanical) ↔ watts BTU per hour ↔ kilowatts

bit · B · kB · MB · GB · TB · KiB · MiB · GiB · TiB · kbit · Mbit · Gbit

Gigabytes ↔ megabytes Gibibytes ↔ gigabytes Megabits ↔ megabytes

ms · s · min · h · d · wk · mth · yr

Hours ↔ minutes Days ↔ hours Weeks ↔ days

l/100 km · l/mil · km/l · mpg (US) · mpg (UK)

Litres per 100 km ↔ miles per US gallon Litres per 100 km ↔ kilometres per litre Miles per imperial gallon ↔ litres per 100 km

° · rad · mrad · gon · ′ · ″ · rev

Degrees ↔ radians Gradians ↔ degrees Degrees ↔ arcminutes

Data transfer rate

bit/s · kbit/s · Mbit/s · Gbit/s · B/s · kB/s · MB/s · GB/s

Megabits per second ↔ megabytes per second Gigabits per second ↔ megabytes per second Megabits per second ↔ gigabits per second

Hz · kHz · MHz · GHz · rpm

Megahertz ↔ gigahertz Hertz ↔ kilohertz Hertz ↔ revolutions per minute

N · kN · kgf · lbf · dyn

Newtons ↔ kilograms-force Newtons ↔ pounds-force

Nm · kgf·m · lb-ft · lb-in · oz-in

Newton metres ↔ pound-feet Newton metres ↔ kilogram-force metres Newton metres ↔ pound-inches

kg/m³ · g/cm³ · kg/l · lb/ft³ · lb/gal

Grams per cubic centimetre ↔ kilograms per cubic metre Grams per cubic centimetre ↔ pounds per cubic foot Pounds per cubic foot ↔ kilograms per cubic metre

pt · px · mm · in · pc

Points ↔ pixels Points ↔ millimetres

Kitchen

Choose an amount, a measure and an ingredient to see what it weighs and how much it is in other measures.

Body measurements

Enter height and weight, and the body mass index is worked out.

Enter a size or the length of the foot, and the equivalents in the other systems appear.

Historical units

Historical units

Pick a unit and a quantity, and it is converted into today’s units. Filter by what is being measured to see only length, area, volume, mass, count or time.