When you need this conversion
Reading scientific papers, lab data, datasheets for electronics (junction temperatures are sometimes given in kelvin), and astronomy.
Reference points
- 0 K = −273.15 °C (absolute zero)
- 77 K = −196.15 °C (liquid nitrogen)
- 273.15 K = 0 °C
- 293.15 K = 20 °C
- 310.15 K = 37 °C (body temperature)
- 373.15 K = 100 °C
Differences stay the same
A change of 10 K equals a change of 10 °C. Only absolute values need the 273.15 offset.
Common mistakes
Converting temperature differences with the offset. A 5 K rise is a 5 °C rise, not −268.15 °C.
Rounding the offset to 273. It’s fine for rough estimates, but results differ by 0.15.
For Fahrenheit, first convert to Celsius, then use Celsius to Fahrenheit. For the reverse, use Celsius to kelvin.