About Temperature Scales

Celsius (°C) is used by most of the world; water freezes at 0 °C and boils at 100 °C. Fahrenheit (°F) is used in the US; water freezes at 32 °F and boils at 212 °F. Kelvin (K) is the SI absolute scale used in science — 0 K is absolute zero (−273.15 °C). Rankine (°R) is the imperial absolute scale.

Conversion Formulas

  • °C → °F: (°C × 9/5) + 32
  • °F → °C: (°F − 32) × 5/9
  • °C → K: °C + 273.15
  • K → °C: K − 273.15

Key Reference Points

  • Absolute zero: 0 K / −273.15 °C / −459.67 °F
  • Body temperature: 37 °C / 98.6 °F
  • Room temperature: ~22 °C / ~72 °F
  • Boiling water: 100 °C / 212 °F / 373.15 K
  • Oven (moderate): 180 °C / 356 °F