Unit converter

Unit converter features

• 01

  Five everyday categories

  Switch between Length (mm to miles), Weight (mg to stones), Temperature (°C / °F / K), Volume (ml to gallons, with US and UK gallons) and Area (mm² to square miles). No digging through dozens of obscure units.

• 02

  Temperature, done right

  Celsius ↔ Fahrenheit ↔ Kelvin uses true offset conversion, not linear multiplication. So −40 °C and −40 °F match exactly, and 273.15 K converts to 0 °C as it should.

• 03

  Swap, copy, move on

  One click to swap the source and target units, another to copy the result to your clipboard. Ideal for recipe scaling, travel-weight checks or school homework.

Unit converter FAQ

How do I convert meters to feet?

Pick Length, set the source to meters and the target to feet, then type your value. The converter uses the exact factor (1 m = 3.28084 ft) and shows the result instantly.

How do I convert Celsius to Fahrenheit?

Open the Temperature tab, set the source to Celsius and the target to Fahrenheit. The formula (°C × 9/5) + 32 is applied automatically, so 100 °C becomes 212 °F.

What's the difference between US and UK gallons?

A US gallon is 3.7854 liters; a UK (imperial) gallon is 4.5461 liters — about 20% larger. The converter lists both, so recipes from US and UK sources come out the way they were intended.

Does it support metric and imperial together?

Yes. Every category mixes metric and imperial units in the same list, so you can convert meters to feet, kilograms to pounds, or square meters to acres without switching modes.

Is this unit converter accurate?

Conversions use exact SI-defined factors (for example 1 inch = 0.0254 m exactly). Results are displayed with up to 10 significant digits so you can trust them for engineering, cooking and schoolwork.

Is the unit converter free?

Yes. No sign-up, no limits, no watermarks — every Handytool is free to use.