Online Unit Converter
Convert length, weight, temperature, volume, speed and more.
Unit Converter
Universal unit converter engine
What does Unit Converter do?
One converter covering twelve measurement categories with exact internationally defined factors. Pick a category, choose your units, and every conversion is shown with the formula and a quick-reference table.
How to Use Unit Converter
- 1Pick a categoryLength, weight, temperature and so on.
- 2Choose your unitsConvert from one to another, or swap them.
- 3Enter a valueEvery unit in the category updates at once.
Key Features
- Twelve categories with over 120 units in total
- Exact factors from the international yard and pound agreement
- Adjustable precision, with rounding applied only at display
- All other units in the category shown at once
- Ambiguous units listed separately — US and imperial gallons never silently merged
Frequently Asked Questions
How accurate are these conversions?
Exact where an exact factor is defined. One inch is exactly 25.4 mm and one pound is exactly 0.45359237 kg by international agreement, and everything imperial derives from those. Rounding happens only at the precision you choose for display.
Why are there two kinds of gallon?
The US liquid gallon is 3.785 litres and the imperial gallon is 4.546 litres — a 20% difference. The same split applies to pints, quarts and fluid ounces, so both are listed as separate units.
Which units are not exact?
Anything defined by a physical measurement rather than by agreement: Mach depends on air temperature, mmHg depends on gravity and mercury density, and the astronomical parsec derives from a measured constant. Those units say so in their names.
Can I convert currency here?
No. Exchange rates change constantly and a stale rate is worse than none. This converter covers only units with fixed, defined relationships.
Conversions run in your browser using fixed, published factors. Nothing you enter is transmitted, and the tool keeps working with the network disconnected.
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