Measurement
Same quantity
Whichever unit you need
160 units across 27 converters, grouped into 7 families. Type a number and the answer is already there — the arithmetic runs on your own device.
Basic Unit ConversionsKitchen, road and weather units — distance, mass, heat, area, volume, speed and time.LengthWeightTemperatureAreaVolume7 converters · 56 unitsMechanical UnitsForce, torque and pressure, from a tyre gauge to a structural load case.ForceTorquePressure3 converters · 19 unitsData & Storage UnitsFile sizes and link speeds, in decimal prefixes and binary ones side by side.Data StorageBandwidth2 converters · 18 unitsElectrical UnitsVolts, amps, ohms, farads, coulombs and henries across every prefix you meet.VoltageCurrentResistanceCapacitanceElectric Charge6 converters · 26 unitsEnergy & PowerJoules through to kilowatt-hours, watts through to horsepower, plus fuel economy either way round.EnergyPowerFuel Consumption3 converters · 19 unitsLight & Lighting UnitsLux, lumens, candela and nits for photography, room lighting and display specs.IlluminanceLuminanceLuminous FluxLuminous Intensity4 converters · 11 unitsAdvanced UnitsAngles and frequencies for maths, navigation, audio work and radio.AngleFrequency2 converters · 11 units
How it behaves
Answers while you type
There is no convert button. Change a digit or swap a unit and the result has already moved.
Factors from the SI tables
Ratios come from the published definitions, and temperature uses its real formulas rather than a single multiplier.
Stays on your device
Every calculation happens in the browser. No value you enter is sent to us or stored anywhere.
Made for a phone
Big targets, readable figures and a one-tap swap, so it works the same standing in a workshop as at a desk.
Need the files themselves changed rather than the numbers? The converters handle documents, images, audio, video and archives.
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