How the Unit Converter Works
This tool converts between the most common units of measurement: length, weight, volume, and temperature. It supports conversions between the metric system (used in most of the world) and the imperial system (used in the United States and partially in the UK).
Length Units
- Kilometers to Miles: 1 km = 0.6214 mi | 1 mi = 1.6093 km
- Meters to Feet: 1 m = 3.2808 ft | 1 ft = 0.3048 m
Weight Units
- Kilograms to Pounds: 1 kg = 2.2046 lb | 1 lb = 0.4536 kg
Volume Units
- Liters to US Gallons: 1 l = 0.2642 gal | 1 gal = 3.7854 l
Temperature
Temperature conversion uses specific formulas, not simple multiplication:
- °C to °F: multiply by 9/5 and add 32
- °F to °C: subtract 32 and multiply by 5/9
Reference points: 0°C = 32°F (water freezing), 100°C = 212°F (water boiling), 37°C = 98.6°F (body temperature).
The International System of Units
The International System of Units (SI) uses the meter as the base unit of length, defined as the distance traveled by light in a vacuum in 1/299,792,458 of a second. The kilogram is the base unit of mass, redefined in 2019 based on the Planck constant.