Math and measurement tools
Unit Converter
Convert length, mass, temperature, area, volume, speed and storage units. Swap direction, compare units and distinguish US, Imperial, decimal and binary measures.
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How to use this tool
1. Choose a measurement category, then select the source and destination units. Common conversion presets fill a sample value.
2. Enter the value and select Convert. Negative values are accepted only for temperatures at or above absolute zero.
3. Read the main result and the equivalent values in other units. Swap units to reverse the direction while keeping your entered amount.
How conversion works
Most conversions multiply by the source unit’s base-unit factor and divide by the destination factor. Temperature conversions also apply an offset. Area units square length factors; volume units cube them. Results use up to twelve significant digits.
Worked examples
10 centimetres is approximately 3.93700787402 inches. 20 °C equals 68 °F. One US liquid gallon is 3.785411784 litres, while one Imperial gallon is 4.54609 litres. One MiB is 1,048,576 bytes; one MB is 1,000,000 bytes.
Questions and assumptions
Which unit system should I choose?
US liquid and Imperial gallons and fluid ounces are explicitly separate. Mass ounces mean avoirdupois, not troy ounces. Digital decimal prefixes use powers of 1,000; binary prefixes use powers of 1,024. Storage sizes are distinct from transfer rates.
Limits and precision
Enter decimal notation without commas or exponent notation. Supports zero or magnitudes from 0.000000000001 to 1,000,000,000,000; non-temperature inputs must be non-negative. Tiny or large results may use scientific notation. It does not convert currencies or infer density to convert mass to volume.
Sources and further reading
Built and maintained by Custom Logic. Page updated .