How to convert temperature
Temperature conversions move between Celsius, Fahrenheit and Kelvin. Each scale measures the same thing from a different zero point and step size, so converting is just a matter of applying the right formula. This tool converts between all three instantly.
The formulas
Celsius to Fahrenheit: F = C x 9/5 + 32. Fahrenheit to Celsius: C = (F - 32) x 5/9. Celsius to Kelvin: K = C + 273.15.
Worked example
100 Celsius is 212 Fahrenheit, the boiling point of water, and 373.15 Kelvin. Zero Celsius is 32 Fahrenheit and 273.15 Kelvin, the freezing point.
Quick reference
Body temperature of 37 Celsius is 98.6 Fahrenheit. Room temperature around 20 to 22 Celsius is about 68 to 72 Fahrenheit. For a rough mental estimate of Celsius to Fahrenheit, double it and add 30.
Frequently asked questions
What is the formula for Celsius to Fahrenheit?
Multiply the Celsius value by 9/5 and add 32. So 100 C is 100 x 9/5 + 32 = 212 F.
What is Kelvin?
Kelvin is the scientific scale that starts at absolute zero. Convert from Celsius by adding 273.15, so 0 C is 273.15 K.
Is there a quick mental estimate?
To roughly convert Celsius to Fahrenheit, double it and add 30. It is close for everyday temperatures.