Unit Converter
- Choose a category: length, mass, volume, temperature, area, speed, time, data, energy, pressure or angle.
- Select the source and target units.
- Type the value. Conversion is immediate.
Every category has a base unit — metre for length, kilogram for mass, litre for volume. Converting means multiplying by the source unit’s factor to reach the base, then dividing by the target unit’s factor.
This keeps precision and avoids a combinatorial explosion: instead of storing every possible pair within a category, one factor per unit is enough.
Temperature is the exception. It is not a proportional scale: zero degrees Celsius is not the absence of heat. Conversion therefore needs an offset as well as a factor — multiplying alone is not enough.
An ounce can measure mass or volume, and the two are unrelated. The US fluid ounce and the British one also differ from each other.
The US gallon holds about 3.785 litres; the British imperial gallon about 4.546. A 20% difference that has caused errors in recipes, fuel consumption figures and engineering documentation.
The ton has three definitions: metric, US short and British long. This tool uses the metric tonne of 1000 kilograms.
Whenever a unit has a regional variant, confirm which one is in use before trusting the number.
This is the most common divergence in data units. Drive manufacturers use powers of 1000: one terabyte is 1,000,000,000,000 bytes.
Operating systems often display powers of 1024, which is why a 1 TB drive shows up as roughly 931 GB. No space is missing — the two counts are simply different.
Units with "bi" in the name, such as kibibyte and mebibyte, exist precisely to name the powers of 1024 without ambiguity.
Frequently asked questions
Because the manufacturer counts in powers of 1000 while the operating system displays powers of 1024. No space was lost: they are two ways of counting the same number of bytes.
Because the scales do not share a zero point. Zero Celsius is not the absence of heat, so conversion needs an offset as well as a factor.
No. The US gallon is about 3.785 litres and the British about 4.546 — nearly 20% apart.
Both exist and they are unrelated. The mass ounce is about 28.35 grams; the fluid ounce measures volume and still differs between US and British standards.
No. Conversion happens in your browser.