Convert length, weight, temperature, volume, speed, and digital data between all common units.
Six categories, all the everyday units:
Pick a category, enter a value, choose the from- and to-units, and convert. Every conversion goes through a precise base unit (metres, kilograms, litres, and so on) so chained rounding errors never creep in.
| Rule of thumb | Exact |
|---|---|
| 1 inch ≈ 2.5 cm | 2.54 cm |
| 1 kg ≈ 2.2 lbs | 2.20462 lbs |
| 1 mile ≈ 1.6 km | 1.60934 km |
| 1 US cup ≈ 240 ml | 236.588 ml |
| °F ≈ °C × 2 + 30 | °C × 9/5 + 32 |
Temperature is not proportional. Unlike every other category, temperature scales have different zero points, so you can't convert with a single multiplier — 0 °C is 32 °F, not 0 °F. The converter applies the full offset formula automatically.
Data units are powers of 1024 here. This tool uses the binary convention (1 KB = 1024 bytes) that operating systems traditionally report, while drive manufacturers advertise in decimal (1 KB = 1000 bytes) — which is why a "1 TB" drive shows up as roughly 931 GB on your computer.
Volume units follow US definitions — a US gallon is 3.785 litres versus the UK's 4.546, and cups differ too. Length and weight units (inches, feet, pounds) are identical in both systems, so only volume needs care.
Drive makers count 1 TB as 10¹² bytes; operating systems traditionally count in powers of 1024. Both are 'correct' — this converter uses the binary (1024) convention, matching what your OS reports.
Conversions use full-precision factors (e.g. 1 inch = 0.0254 m exactly) and display up to six decimal places with trailing zeros trimmed, which is more precision than any everyday measurement needs.