Unit converter — metric and imperial, both directions
Convert between metric and imperial units across six categories: length, weight/mass, temperature, volume, area, and speed. Built for recipes, travel, schoolwork, DIY and engineering — any time you need to move between systems quickly and accurately.
How it works
Every category defines a single base unit and converts through it. Lengths route through metres, weights through kilograms, temperatures through Celsius, volumes through litres, areas through square metres, and speeds through metres per second. Your input is first converted to the base unit, then from the base unit to your target, so any pair within a category works without a special-case formula. Constants are exact where a definition exists (1 inch = 0.0254 m, 1 mile = 1609.344 m, 1 lb = 0.453592 kg). Both fields are live — edit either side — and the ⇄ button swaps the pair. Results are shown to 8 significant figures with trailing zeros removed.
Example
Convert 5 miles to kilometres: 5 × 1609.344 m = 8046.72 m = 8.04672 km. Or 70°F to Celsius: (70 − 32) × 5/9 = 21.11°C.
| From | To | Factor / formula | Example |
|---|---|---|---|
| 1 inch | cm | × 2.54 | 12 in = 30.48 cm |
| 1 mile | km | × 1.609344 | 5 mi = 8.04672 km |
| 1 kg | lb | ÷ 0.453592 | 10 kg = 22.05 lb |
| °C → °F | — | × 9/5 + 32 | 20°C = 68°F |
| 1 L | US gal | ÷ 3.78541 | 10 L = 2.642 gal |
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