Temperature formulas
Fahrenheit from Celsius is (C × 9/5) + 32. Celsius from Fahrenheit is (F − 32) × 5/9. Kelvin equals Celsius plus 273.15.
Everyday reference points
- Water freezes at 0 °C or 32 °F
- Water boils near 100 °C or 212 °F at standard pressure
- 0 K is absolute zero
Celsius and Kelvin increments
A change of one degree Celsius is the same size as a change of one kelvin; only their zero points differ. Kelvin values are written without a degree symbol.
Real-world conditions
Boiling points vary with pressure and altitude, and measured temperatures carry instrument uncertainty. Use calibrated equipment and the required standard for scientific or safety-critical work.