ToolWren › Temperature

Temperature Converter

Convert temperatures between Celsius, Fahrenheit and Kelvin — for cooking, science, weather and travel.

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How to use the Temperature

Enter the number you want to convert in the Value field.
Pick the unit you're converting From and the unit you want To.
Read the converted result, or use ⇅ to swap the two units.
Check the All units table to see your value expressed in every supported unit at once.

Privacy: this tool runs entirely in your browser. Your input is never sent to, received by, or stored on any server — there are no uploads and no tracking of what you enter.

About Temperature

The three scales

Celsius is used by most of the world, Fahrenheit mainly in the US, and Kelvin in science (it starts at absolute zero). Water freezes at 0C / 32F / 273.15 K.

The formulas

F = C x 9/5 + 32. C = (F - 32) x 5/9. K = C + 273.15. The scales have different zero points, so it is not a simple multiply.

Quick references

20C = 68F (room), 37C = 98.6F (body), 100C = 212F (boiling).

Frequently asked questions

How do I convert C to F?

Multiply by 9/5 and add 32 — e.g. 25C = 77F.

What is absolute zero?

0 K = -273.15C = -459.67F, the lowest possible temperature.

Why is it not a simple ratio?

Each scale has a different zero point, so conversion needs an offset.