About this temperature converter
Convert a temperature between Celsius, Fahrenheit, and Kelvin by entering a value and choosing the units to convert from and to. This covers everyday conversions like checking a weather forecast reported in an unfamiliar scale, following a recipe from another country, or converting a scientific reading to Kelvin. The tool validates that a Kelvin or converted value never falls below absolute zero, the coldest physically possible temperature, and reports a clear error if the input would require it.
How the temperature converter works
Every conversion passes through Celsius as an intermediate step: Fahrenheit to Celsius is (F − 32) × 5⁄9, and Celsius to Kelvin adds 273.15. The reverse formulas convert back out to the requested unit.
Temperature Converter examples
100 °C to °F
212
0 °C to K
273.15
Limitations & privacy
Rejects any value that would fall below absolute zero (−273.15 °C, −459.67 °F, or 0 K). Results are shown to two decimal places, which may round very precise scientific values.
Inputs and results stay in this browser. Only tool identifiers are stored for your recently used tools. You can clear that history from the directory.
Temperature Converter: frequently asked questions
What is absolute zero?
Absolute zero is 0 Kelvin, −273.15 °C, or −459.67 °F: the coldest temperature theoretically possible, where this tool stops accepting a colder input.
Can I convert Fahrenheit directly to Kelvin?
Yes. Choose Fahrenheit as the source and Kelvin as the target; the tool converts through Celsius internally and returns the Kelvin value.
Why does my result have decimals?
Fahrenheit and Celsius conversions rarely land on whole numbers because of the 5⁄9 scaling factor. Results are rounded to two decimal places for readability.
Updated September 20, 2026