Unit converter
Converts between metric and imperial units – from inches to centimetres, pounds to kilograms or Fahrenheit to Celsius.
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How it works
- Choose a category and enter a value.
- Choose the source and target unit.
- Click “Convert” – the table shows the value in all units of the category.
Notes and limitations
- The factors are exact definitions (e.g. 1 inch = 2.54 cm, 1 pound = 0.45359237 kg, 1 US gallon = 3.785411784 l).
- Temperatures are converted with offsets, not just factors; values below absolute zero are rejected.
- US and imperial units differ (gallon, fluid ounce); both are listed separately where relevant.
Frequently asked questions
Why do US and UK gallons differ?
They are historically different units: 1 US gallon = 3.785 l, 1 imperial (UK) gallon = 4.546 l.