Convert between metric and imperial units instantly — length, weight, temperature, volume, area, speed, and data. Every result includes a full reference table.
Unit conversion multiplies a value by a conversion factor — the ratio between two units. For example, 1 kilometre = 0.621371 miles, so to convert 5 km to miles, multiply 5 × 0.621371 = 3.107 miles. Temperature is the exception: it uses offset formulas (°C to °F = multiply by 9/5 then add 32) because the scales don't share a common zero point.
The metric system (SI) is used by most of the world and is based on powers of 10, making conversions within the system straightforward. The imperial system (used primarily in the US, UK for some measures, and Myanmar) uses less consistent relationships between units.
Multiply the Celsius value by 9, divide by 5, then add 32. So 25°C = (25 × 9/5) + 32 = 45 + 32 = 77°F. To go the other way, subtract 32 then multiply by 5/9.
1 mile = 1.60934 km. Conversely, 1 km = 0.621371 miles. A quick mental shorthand: multiply miles by 1.6 for km, or multiply km by 0.6 for an approximate mile value.
In the SI standard, 1 gigabyte (GB) = 1,000,000,000 bytes. In binary computing, 1 gibibyte (GiB) = 1,073,741,824 bytes. This calculator uses the SI (decimal) standard for data units, which matches how storage manufacturers label drives.