Unit Converter
Free online unit converter for length, weight, area and temperature, covering millimetres to miles, grams to pounds, ounces and stone, square feet to acres, and Celsius/Fahrenheit/Kelvin. Enter a value and convert instantly — for study, cooking, travel, shopping and engineering. CalculatorRuns locally
Use this tool
How to use
- Pick a category (length / weight / area / temperature).
- Choose the source unit on the left, enter a value, and choose the target unit on the right.
- The result updates live; tap “Swap” to reverse the conversion.
Frequently asked questions
Which units are supported?
Length spans millimetres to miles plus inches, feet and yards; weight covers grams, kilograms, tonnes, ounces, pounds and stone; area covers square metres, square feet, acres and hectares; temperature converts Celsius, Fahrenheit and Kelvin.
How many grams in an ounce / pounds in a kg?
One ounce is 28.3495 g and one pound is 453.592 g (about 0.4536 kg); these factors are built in.
Why is temperature different?
Temperature uses an offset formula rather than a simple ratio; Celsius, Fahrenheit and Kelvin each use their correct formula.