Temperature Converters
Temperature is the one conversion that cannot be done by simple multiplication, because the Celsius and Fahrenheit scales start at different zero points. Celsius is used for weather and cooking in most of the world, Fahrenheit in the United States, and Kelvin in science and engineering. The converters here apply the correct offset and ratio for each scale, so you can safely convert oven temperatures, forecasts, body temperature and lab values.
All temperature converters
Things to know about temperature conversions
- Temperature scales do not share a zero point, so you cannot convert with multiplication alone. Celsius to Fahrenheit needs both a scale factor of 1.8 and an offset of 32.
- The scales agree at exactly -40: that temperature reads the same in Celsius and Fahrenheit.
- Kelvin uses the same degree size as Celsius, but starts at absolute zero. Add 273.15 to a Celsius value to get kelvins.
- For oven settings, round to the nearest 5 or 10 degrees. Fan ovens usually run about 20 °C (25 °F) cooler than conventional ovens.
Temperature reference points
| Reference | °C | °F | K |
|---|---|---|---|
| Absolute zero | -273.15 | -459.67 | 0 |
| Water freezes | 0 | 32 | 273.15 |
| Comfortable room | 21 | 69.8 | 294.15 |
| Normal body temperature | 37 | 98.6 | 310.15 |
| Water boils (sea level) | 100 | 212 | 373.15 |
Temperature units explained
- Degree Celsius (°C)
- Celsius sets 0 °C at the freezing point of water and 100 °C at its boiling point at sea level. It is used for weather, cooking and everyday temperatures in nearly every country.
- Degree Fahrenheit (°F)
- Fahrenheit puts water's freezing point at 32 °F and boiling point at 212 °F. It is still used for weather, cooking and body temperature in the United States.
- Kelvin (K)
- Kelvin is the SI base unit of temperature. Zero kelvin is absolute zero, the coldest possible temperature, and one kelvin has the same size as one degree Celsius.