Temperature converter
Convert between Celsius, Fahrenheit and Kelvin with the exact formulas — not rounded shortcuts. Type any reading, including negatives, and see all three scales side by side.
| Scale | Value |
|---|
How to convert temperature
Enter the reading
Type the temperature you have. Minus signs and decimals both work.
Pick the scales
Select the scale you're in and the one you want; swap flips the direction.
Compare all three
Read the converted value, and see Celsius, Fahrenheit and Kelvin together in the table.
The formulas behind it
Temperature isn't a simple ratio like length or weight, because each scale starts from a different zero point. That's why converting needs a formula rather than a single multiplier:
°F = (°C × 9/5) + 32 · °C = (°F − 32) × 5/9 · K = °C + 273.15 · °C = K − 273.15.
Reference points worth memorizing
Water freezes at 0 °C = 32 °F = 273.15 K and boils at 100 °C = 212 °F = 373.15 K. Normal body temperature is about 37 °C = 98.6 °F. Absolute zero, the coldest possible, is 0 K = −273.15 °C = −459.67 °F.
The one temperature that's the same in two scales
−40 °C and −40 °F are exactly equal — the only point where the Celsius and Fahrenheit scales meet. It's a handy sanity check that a converter is doing the maths right.
Temperature converter FAQ
How do I convert Celsius to Fahrenheit?
Multiply the Celsius value by 9/5 and add 32. For example, 20 °C becomes 68 °F. Convee applies the exact formula automatically.
What is Kelvin used for?
Kelvin is the scientific scale that starts at absolute zero. It shares the same step size as Celsius, so you convert simply by adding or subtracting 273.15.
Can it handle negative temperatures?
Yes. Enter any negative reading, such as −18 °C for a freezer, and every scale updates correctly.
Is anything sent to a server?
No. The formulas run in your browser, so your readings stay entirely on your device.