📐 Unit Converter

How to use the Unit Converter

Convert between metric and imperial units across length, weight, temperature, area, volume and speed, with the common conversions in one place.

How it works

Conversions go through a base unit: length through metres, mass through kilograms, volume through litres. Temperature is the exception because Celsius and Fahrenheit are offset as well as scaled, so the conversion is F = C × 9/5 + 32 rather than a simple ratio. There is no absolute zero on the Fahrenheit scale, which is why the offset exists at all.

When to use it

Use it for cooking where recipes mix systems, for travel and packing, for construction and furniture dimensions, and for comparing product specifications across regions.

Worked example

Conversions worth memorising:

Assumptions and limitations

Cups and spoons measure volume, not weight, and a cup of flour weighs roughly half what a cup of water does, so baking should use a scale. The US and UK use different gallon sizes, and an Australian tablespoon differs again. Temperature changes of 1°C and 1°F are not the same magnitude, which matters when adjusting recipes. Imperial units are no more accurate than metric; they are simply defined differently.