Unit Converter

Convert between common units for length, mass, temperature, volume, area, speed, time and data. Instant two-way conversion with precision control, quick swap, shareable link and CSV export.

Quick reference

1 metre = 100 cm = 1000 mm • 1 inch = 2.54 cm • 1 mile = 1.60934 km • 1 foot = 0.3048 m

1 kilogram = 1000 g • 1 lb = 16 oz ≈ 0.453592 kg • 1 stone = 14 lb ≈ 6.35029 kg

°C to °F: multiply by 9/5 and add 32 • K = °C + 273.15

1 litre = 1000 ml • 1 US gallon ≈ 3.78541 L • 1 UK gallon ≈ 4.54609 L

1 m² = 10.7639 ft² • 1 hectare = 10,000 m² • 1 acre ≈ 4046.86 m²

mph to km/h × 1.60934 • m/s to km/h × 3.6 • knots to km/h × 1.852

1 hour = 60 min = 3600 s • 1 day = 24 h • 1 week = 7 days

1 KB = 1024 B • 1 MB = 1024 KB • 1 GB = 1024 MB • 1 TB = 1024 GB

About this converter

This unit converter is built for speed and clarity. Pick a category, type a value and see the conversion update instantly. You can convert in either direction, swap units with one click and adjust the number of decimal places to suit how you want to copy figures into your documents.

The temperature converter uses the correct linear offsets between Celsius, Fahrenheit and Kelvin. All other categories use scale factors relative to a base unit so results are consistent. Your selections are reflected in the address bar which lets you bookmark or share a prefilled setup. The CSV export captures your inputs and outputs for quick notes.

If there is a unit you want added, tell us and we will include it in an update.

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