Unit Converter
Convert length, weight, volume, temperature, area, speed and cooking units. Use metric conversion and US units. The result shows as you type.
- +Free. No sign-up.
- +No limits.
- +Your data stays on your device.
- +Exact factors from NIST.
Exact factors
Every unit has an exact definition from NIST. For example, 1 inch is exactly 2.54 cm, and 1 pound is exactly 0.45359237 kg.
The converter shows up to 6 significant digits. It does not use an exponent for normal numbers.
Metric conversion
The metric system uses powers of ten. To change between km, m, cm and mm, move the decimal mark.
To change between metric and US units, use the factors above. The converter does this for you.
How to use it
- Choose a category: for example Length or Temperature.
- Choose the unit in From and the unit in To. Press Swap to change them.
- Type your number. The result changes as you type.
- For cooking, choose an ingredient to change between cups and grams.
Sources
The weight of 1 cup of flour, sugar, butter or rice is a reference value. Water is 1 g in 1 mL.
Questions
How do I convert one unit to another?
Choose a category. Choose the unit you have in From and the unit you want in To. Type your number. The result shows at once.
Are the conversions exact?
Yes. Every factor is an exact definition from NIST. For example, 1 inch is exactly 2.54 cm. The page shows up to 6 significant digits.
Can I type a comma as the decimal mark?
Yes. You can type 72,5 or 72.5. A number such as 1,000 is not accepted, because a comma can also be a thousands mark.
How do I change cups to grams?
Choose Cooking. Choose cup in From and g in To. Then choose an ingredient. A cup of flour and a cup of sugar do not weigh the same.
Does the converter send my numbers to a server?
No. The converter works in your browser and sends nothing. The numbers you type stay on your device. The page saves nothing. Read more about privacy.