Unit Converter

Convert length, weight, temperature, area, volume, and speed between metric and imperial units instantly.

Students, travellers, cooks, and engineers converting everyday measurements.

How to use it

  1. Pick a category

    Choose length, weight, temperature, area, volume, or speed.

  2. Select the units

    Choose the unit to convert from and the unit to convert to; use the swap button to reverse the direction.

  3. Enter a value

    Type your value and read the converted result instantly.

Why use this tool?

Converting between units from memory is where small, costly mistakes creep in — a recipe in cups when you only have scales, a distance in miles when your car shows kilometres, a temperature in Fahrenheit when you think in Celsius. The conversion factors are easy to half-remember and easy to apply the wrong way round, and temperature is especially tricky because it needs an offset, not a simple multiplication. This converter removes the guesswork across the everyday categories — length, weight, temperature, area, volume, and speed. Pick a category, choose the units to convert from and to (with a swap button to reverse them), and the result updates instantly. It uses precise SI conversion factors for accuracy, and handles temperature with the correct offset formulas for Celsius, Fahrenheit, and Kelvin rather than treating them as simple ratios. Everything runs in your browser, with no limits and no sign-up.

Common use cases

Travel

Convert miles to kilometres, or Fahrenheit to Celsius, when you’re somewhere that uses the other system.

Cooking & baking

Switch recipe amounts between cups, millilitres, grams, and ounces.

Study & work

Convert science and engineering units accurately for homework, labs, and reports.

DIY & home

Move between feet/inches and metres/centimetres for measuring and building.

Fitness & health

Convert weights between kilograms and pounds, or distances between miles and kilometres.

Frequently asked questions

How accurate are the conversions?

They use standard SI conversion factors and are accurate to six decimal places.

Does it convert temperature correctly?

Yes. Temperature uses proper offset formulas (e.g. °F = °C × 9/5 + 32), not simple ratios, for Celsius, Fahrenheit, and Kelvin.

Which categories are supported?

Length, weight/mass, temperature, area, volume, and speed, each with the common metric and imperial units.

Can I reverse the conversion quickly?

Yes — the swap button flips the "from" and "to" units instantly.

Does it handle US vs UK units that share a name?

Where units differ (such as US vs imperial gallons), they are listed separately so you pick the correct one.

Is my data uploaded?

No. All conversions run in your browser.

Does it work offline once loaded?

The conversion maths is fully client-side, so it keeps working without sending anything to a server.

Is it free?

Yes — completely free, with no limits or sign-up.

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