How to use this calculator
Choose a source and destination from the same category, then enter a value.
Formula and method
For multiplicative units: output = input × source-to-base factor / target-to-base factor. Temperature uses offsets via kelvin.
Worked example
1 km = 0.621371192237 mi; 32 °F = 0 °C.
Assumptions and supported scope
Defined units only; cross-category conversion is invalid. Temperature values below absolute zero are rejected. Data sizes are bytes. Factors use NIST exact definitions where available; displayed decimals are approximations.
Method references
Method and worked example checked against the calculator implementation. About our methods · Report a correction