Unit Converter
The everyday conversions in one small tool: metres to feet, kilograms to pounds, Celsius to Fahrenheit, litres to gallons — with the exact factors, not rounded approximations.
100% private — everything runs in your browser, nothing is ever uploaded.
What this tool does
A recipe calls for 200 grams but the kitchen scale reads ounces, a US property listing gives square footage while a European buyer thinks in square metres, and a weather forecast switches between Celsius and Fahrenheit mid-conversation. Small conversion errors are easy to make and surprisingly consequential when they land in a form or an order. This tool covers the everyday categories — length, weight, temperature and volume — using exact factors rather than rounded approximations, and updates the result as you type. It is deliberately limited to conversions people actually need in daily life: metres to feet, kilograms to pounds, Celsius to Fahrenheit, litres to gallons and their counterparts. For scientific or engineering work with derived units, a specialised reference is still the right place to check the factor.
How to use it in three steps
- Choose a category: length, weight, temperature or volume.
- Enter the value and pick the units to convert from and to. The result updates as you type, so you can try a second pair without clearing the field.
- Read the converted value and copy it into your document. For temperature, remember the scales have different zero points, so a simple multiplication would be wrong. State the unit next to the converted figure wherever you paste it, since a bare number is easy to misread later.
Questions people ask
Why does Fahrenheit conversion not look like a simple ratio?
Celsius and Fahrenheit have both different step sizes and different zero points, so the conversion includes an offset. Length, weight and volume conversions are pure ratios and can be scaled directly.
Are US and imperial gallons the same?
No. A US liquid gallon and an imperial gallon are different volumes. Check which one your source means before using the result in a recipe, a fuel calculation or a shipping form.
Can I convert area or speed units?
This tool covers the four listed categories of everyday single-dimension units. Area and speed are derived units that need their own conversion factors and are outside its scope.
Why do two online converters give slightly different answers?
Some use rounded factors or a shortened intermediate result. This tool applies the defined conversion factors directly, so a value may differ in the last decimal place from a site that rounds twice. For legal or scientific work, cite the standard your field uses.
Privacy: Conversions are computed in this browser tab from fixed factors with no network request, so recipe quantities, measurements and order figures you enter remain on your own device.
How to use it
- Choose a category: length, weight, temperature or volume.
- Enter a value and pick the units to convert from and to.
- The result updates as you type.
Why it stays private
Unit conversion is arithmetic on a number you typed — there is nothing to send anywhere, and the tool works offline once loaded.
Questions
Are the conversion factors exact?
The length, weight and volume factors are the internationally agreed exact definitions (1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Temperature uses the standard formulas, not offsets guessed from memory.
Why does Fahrenheit conversion look different?
Temperature scales have different zero points, so conversion needs multiplication and addition, not just multiplication. The tool applies the exact formulas both ways.
Are US and UK gallons different?
Yes, and this tool converts using US gallons (3.785 litres). An imperial (UK) gallon is about 4.546 litres — 20% larger. Watch out for this when following old British recipes.