Unit Converter

Convert between metric and imperial units across seven categories: length, weight, temperature, volume, area, speed, and time.

Common conversions

Length

1 inch= 2.54 cm
1 foot= 0.3048 m
1 yard= 0.9144 m
1 mile= 1.609344 km
1 nautical mile= 1.852 km

Weight

1 ounce= 28.3495 g
1 pound= 0.453592 kg
1 stone= 6.35029 kg
1 short ton (US)= 907.185 kg

Temperature

°F = °C × 9/5 + 32  |  °C = (°F − 32) × 5/9  |  K = °C + 273.15

Frequently asked questions

How accurate are these conversions?

The conversion factors used here come from international standards (NIST and BIPM) and are accurate to at least 6 significant figures. For most everyday uses — cooking, travel, fitness — they are exact for practical purposes.

What's the difference between a US gallon and a UK gallon?

A US liquid gallon is 3.78541 liters; a UK (imperial) gallon is 4.54609 liters — about 20% larger. The same applies to pints and fluid ounces. This converter uses US customary units by default but includes UK variants for liquids.

Why does temperature use a different formula than other categories?

Most units are linear (multiply by a factor). Temperature scales have different zero points — 0°C is not 0°F — so you need both a multiplication and an offset.