Unit Converter
Convert length, weight, temperature, volume and speed between metric and imperial units — instantly.
Convert units
All units in this category
Quick conversion references
Length: 1 m = 3.28084 ft; 1 km = 0.621371 mi; 1 in = 2.54 cm.
Weight: 1 kg = 2.20462 lb; 1 oz = 28.3495 g.
Temperature: °F = °C × 9/5 + 32.
Volume: 1 gal (US) = 3.78541 L.
Frequently asked questions
How many feet are in a meter?
One meter equals 3.28084 feet. One foot equals 0.3048 meters.
How do you convert Celsius to Fahrenheit?
Multiply Celsius by 9/5 and add 32. For example, 20°C = 68°F. To go back, subtract 32 and multiply by 5/9.
How many pounds are in a kilogram?
One kilogram equals 2.20462 pounds. One pound equals 0.453592 kilograms.
How many ounces are in a gallon?
One US gallon equals 128 US fluid ounces. Note the UK (imperial) gallon is larger at 160 imperial fluid ounces.
What is the difference between a US and imperial gallon?
A US gallon is 3.785 liters; an imperial gallon (UK) is 4.546 liters — about 20% larger. This converter uses US gallons.
How fast is 100 km/h in mph?
100 km/h equals 62.14 mph. Multiply km/h by 0.621371 to get mph.
Why does the US still use imperial units?
Historical inertia and the cost of switching. The US officially adopted the metric system in 1975 but made it voluntary, so everyday life kept feet, pounds and Fahrenheit.