Key takeaways
- 01Five categories in one place: length, weight, temperature, volume and area.
- 02Temperature uses true offset conversion (not just multiplication), so values like -40 °C = -40 °F are exact.
- 03All conversions use exact SI-defined factors and display up to 10 significant digits.
Why Unit Conversion Still Trips People Up
The metric and imperial systems coexist in daily life whether you want them to or not. A US recipe calls for cups and ounces; a fitness tracker reports kilometers; a building plan uses feet and inches; a science class works in Celsius while the weather app shows Fahrenheit. Remembering the exact conversion factor for every combination is unrealistic, and doing it by hand introduces rounding errors.
A good unit converter removes that friction entirely. The tool covers the five categories you actually use — length, weight, temperature, volume and area — with metric and imperial units in the same list. There's no mode-switching or category-hunting; just pick your units and get the number.
How to Convert Units
Conversions are instant — no button to press.
- 01
Pick a category
Choose Length, Weight, Temperature, Volume or Area from the category tabs at the top of the converter.
- 02
Select source and target units
Pick the unit you're converting from and the unit you're converting to. Metric and imperial units appear together in each list.
- 03
Type your value
Enter the number you want to convert. The result updates live with up to 10 significant digits of precision.
- 04
Swap or copy
Use the swap button to reverse the conversion direction instantly. Copy the result to your clipboard with one click.
Common Conversions People Search For
- 01Meters to feet — for property listings and construction plans
- 02Kilograms to pounds — for weight checks, travel baggage limits and fitness
- 03Celsius to Fahrenheit — for recipes, weather and scientific work
- 04Liters to gallons — for cooking, fuel and liquid volume (US and UK gallons both supported)
- 05Square meters to square feet — for floor area and real estate
Accurate, Private and Free
Conversions use exact SI-defined factors — for example, 1 inch is defined as exactly 0.0254 meters — so results are reliable for engineering, cooking, schoolwork and everyday use. Results are displayed with up to 10 significant digits.
The converter runs entirely in your browser. Nothing you type is uploaded or logged. There is no account, no sign-up and no usage limit — Handytool is free to use on any device.
Unit Converter FAQ
How do I convert meters to feet?
Pick the Length category, set the source to meters and the target to feet, then type your value. The converter uses the exact factor of 1 m = 3.28084 ft.
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 is 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 correctly.
Is this unit converter accurate?
Yes. Conversions use exact SI-defined factors and results are displayed with up to 10 significant digits, making them reliable for engineering, cooking and schoolwork.
Does it support metric and imperial in the same list?
Yes. Every category mixes metric and imperial units in one list, so you can convert meters to feet or kilograms to pounds without switching modes.
Is the unit converter free?
Yes. No sign-up, no limits, no watermarks — every Handytool is free.