Celsius or centigrade is a unit of measurement of temperature.
The freezing/melting point of water is about zero degrees celsius (0 °C) at a pressure of 1 atmosphere.
The boiling point of water is about on one hundred degrees celsius (100 °C) at a pressure of 1 atmosphere.
The exact values depend on the water composition (usually the amount of salt) and the air pressure.
Seawater contains salt and the freezing point is reduced below 0 °C.
When boiling water on a mountain above sea level the boiling point is reduced below 100 °C.
The symbol of Celsius degrees is °C.
Celsius to Fahrenheit conversion
0 degrees Celsius is equal to 32 degrees Fahrenheit:
0 °C = 32 °F
The temperature T in degrees Fahrenheit (°F) is equal to the temperature T in degrees Celsius (°C) times 9/5 plus 32:
T(°F) = T(°C) × 9/5 + 32
Example
Convert 20 degrees Celsius to degrees Fahrenheit:
T(°F) = 20°C × 9/5 + 32 = 68 °F
Celsius to Kelvin conversion
0 degrees Celsius is equal to 273.15 degrees Kelvin:
0 °C = 273.15 K
The temperature T in Kelvin (K) is equal to the temperature T in degrees Celsius (°C) plus 273.15:
T(K) = T(°C) + 273.15
Example
Convert 20 degrees Celsius to Kelvin:
T(K) = 20°C + 273.15 = 293.15 K
Celsius to Rankine conversion
The temperature T in degrees Rankine (°R) is equal to the temperature T in degrees Celsius (°C) plus 273.15, times 9/5:
T(°R) = (T(°C) + 273.15) × 9/5
Example
Convert 20 degrees Celsius to degrees Rankine:
T(°R) = (20°C + 273.15) × 9/5 = 527.67 °R
Celsius table
| Celsius (°C) | Fahrenheit (°F) | Temperature |
|---|---|---|
| -273.15 °C | -459.67 °F | absolute zero temperature |
| 0 °C | 32.0 °F | freezing/melting point of water |
| 21 °C | 69.8 °F | room temperature |
| 37 °C | 98.6 °F | average body temperature |
| 100 °C | 212.0 °F | boiling point of water |