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Metric ⇄ Imperial Unit Converter

Switch between metric and imperial measurements in real time.

Processed locally — nothing is uploaded

About Metrics & Unit Converter

Every equivalent updates at once rather than one target at a time, so a single value can be read across all its units together — useful against a recipe, a spec sheet, or instructions written for another country's conventions.

Convert between metric and imperial units — centimetres to inches, kilograms to pounds, Celsius to Fahrenheit and many more — with every equivalent updating as you type. All maths runs locally.

Convert length, weight, temperature, volume, speed and many other units instantly. Type a value and every equivalent updates in real time, so you can move between metric and imperial — centimetres to inches, kilograms to pounds, Celsius to Fahrenheit — without doing the maths.

It covers cooking, travel, DIY, science homework and engineering from one panel. Temperature is the conversion that catches people, because it shifts by an offset as well as a scale — 0 °C is 32 °F, not 0 °F.

Learn how this works

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Frequently asked questions

Which countries still use imperial units?

Only the United States, Liberia and Myanmar use it as the primary system. The UK is genuinely mixed — road distances are in miles and beer in pints, but most other measurements are metric, which is why conversion comes up so often there.

Why is temperature not a simple multiplication?

Because Celsius and Fahrenheit have different zero points as well as different scale sizes, so you need both an offset and a factor: F = C x 9/5 + 32. Most other conversions are a single multiplication.

What is the difference between a US and an imperial gallon?

They are genuinely different: a US gallon is about 3.79 litres, an imperial gallon about 4.55. That is a 20% gap, which catches people out in recipes and fuel-economy figures alike.

Common Use Cases

  • •Following a recipe written for the other measurement system
  • •Converting product dimensions before ordering from abroad
  • •Making sense of distances and weights while travelling

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