How the unit converter works
Every unit in a category is defined relative to one base unit — metres for length, kilograms for weight, and so on. To convert, the calculator turns your value into the base unit, then into the target unit. Temperature is the exception: it uses formulas rather than a simple factor, because the scales have different zero points.
Common conversion factors
length: 1 m = 3.28084 ft = 39.3701 in; 1 mi = 1.60934 km
weight: 1 kg = 2.20462 lb; 1 lb = 16 oz
temp: °F = °C × 9⁄5 + 32; °C = (°F − 32) × 5⁄9
volume: 1 L = 0.264172 US gal; 1 US gal = 3.78541 L
Worked example
Convert 20 °C to Fahrenheit and 5 km to miles:
20 °C: 20 × 9⁄5 + 32 = 36 + 32 = 68 °F.
5 km: 5 ÷ 1.60934 ≈ 3.107 miles.
Tip: swap the from and to units to convert the other way — the relationship is exact in reverse, so 68 °F converts straight back to 20 °C.