Multi-Unit Converter

Convert between units of length, mass, temperature, volume, speed and data storage. Conversions use standard factors and update as you type.

Why temperature works differently

Most unit conversions are a simple multiplication: a kilometre is always 1,000 metres regardless of the value. Temperature is not, because the scales have different zero points as well as different step sizes. Converting Celsius to Fahrenheit requires both a multiplication and an offset, which is why 0°C is 32°F rather than 0°F. This tool handles that separately from the ratio-based categories, so results are correct across the full range including negative values.

Data storage and the 1000 versus 1024 question

There is a genuine ambiguity here worth knowing about. Historically a kilobyte meant 1,024 bytes, following the binary powers computers naturally work in. The SI standard defines the kilo prefix as 1,000, and the binary values were later given separate names — kibibyte, mebibyte, gibibyte. In practice, operating systems and storage manufacturers disagree. This is why a drive sold as 1 TB shows as roughly 931 GB once connected: the manufacturer counted in powers of 1,000 and the operating system displayed powers of 1,024. This tool uses the binary convention, which matches what your computer reports.

Precision and rounding

Results are rounded for readability, which is almost always what you want. Be aware that chaining conversions compounds rounding: converting inches to centimetres to metres and back will not always return exactly the starting number. For anything where precision genuinely matters — engineering tolerances, dosage calculations, legal measurements — convert once directly from the source unit to the target unit rather than stepping through intermediates, and keep the original figure alongside the converted one.

Quick tips

• Switching category clears the fields deliberately, so a value is never reinterpreted in the wrong unit.
• Temperature conversions handle negatives correctly, including below absolute zero warnings.
• A 1 TB drive showing as 931 GB is the 1000-versus-1024 difference, not a fault.
• For critical measurements, convert directly rather than through intermediate units.

Are metric and imperial units both supported?

Yes, all major metric and imperial standard units are built right in.