What you can convert
- Length — between metric and imperial units such as metres, centimetres, feet, inches, and miles.
- Weight — between units like kilograms, grams, pounds, and ounces.
- Temperature — between Celsius, Fahrenheit, and Kelvin.
Length and weight use simple ratio conversions, while temperature uses the proper formulas so the offset between scales is handled correctly.
Frequently asked questions
Why is temperature converted differently from length or weight?
Length and weight scales start at zero, so you convert by multiplying. Temperature scales don't line up at zero — 0°C isn't 0°F — so the converter uses each scale's formula rather than a single ratio.
How precise are the results?
Conversions are shown to several decimal places, which is more than enough for everyday use. Switching the “from” and “to” units simply reverses the calculation.
Why did a result show a dash (—)?
That appears if the selected units don't match the current category. Pick the category first, then choose units from its list and the result updates instantly.
Is my input saved or uploaded?
No. The converter runs entirely in your browser. Nothing you enter is stored or sent to a server.