Fast, free unit conversions

Length, weight, temperature, volume, area, speed, time, digital storage, energy, power, pressure, and HVAC — with formulas and conversion tables for every pair.

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Length

Convert between metric and imperial units of length and distance.

Weight & Mass

Convert between metric and imperial units of weight and mass.

Temperature

Convert between Celsius, Fahrenheit, and Kelvin.

Volume

Convert between metric and US customary units of volume.

Area

Convert between metric and imperial units of area.

Speed

Convert between common units of speed and velocity.

Time

Convert between common units of time.

Digital Storage

Convert between decimal (SI) and binary (IEC) units of digital storage.

Energy

Convert between common units of energy.

Power

Convert between common units of power.

Pressure

Convert between common units of pressure.

HVAC

Convert between the power units used to rate HVAC equipment: BTU/h, tons of refrigeration, kW, watts, and horsepower.