About this tool
This unit converter runs entirely in your browser: nothing is uploaded, and it works offline once the page has loaded. Pick a category, choose the units you are converting between, type a value, and the result updates as you go - along with a full table showing that value converted into every other unit in the category at once. It covers the everyday units people search for most - metres to feet, kilograms to pounds, Celsius to Fahrenheit, litres to gallons, hours to days, and more.
How to use it
- 1 Choose a category (Length, Weight, Temperature, Time, Pressure, Energy and more).
- 2 Pick the unit you are converting from and the unit you want.
- 3 Enter a number - the converted value appears immediately, plus a table with every other unit.
- 4 Swap the two units with the swap button to reverse the conversion.
Frequently asked questions
Is my data sent anywhere?
No. All calculations happen on your device. The page makes no network requests to convert.
How accurate is it?
Conversions use standard internationally-defined factors and full double precision, then round the display to a sensible number of digits.
Does it work offline?
Yes, once the page has loaded it keeps working without a connection.
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Add this free tool to your own website — copy the code below. It stays up to date automatically.
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