Temperature Converter
Convert between Celsius, Fahrenheit, Kelvin, Rankine, and Réaumur with exact formulas. Whether you need everyday cooking conversions or scientific absolute-scale values, our temperature converter handles them all.
Common Temperature Conversions
| From | To |
|---|---|
| 0 °C (freezing) | 32 °F | 273.15 K |
| 100 °C (boiling) | 212 °F | 373.15 K |
| 37 °C (body) | 98.6 °F | 310.15 K |
| 20 °C (room) | 68 °F | 293.15 K |
| -40 °C | −40 °F | 233.15 K |
| −273.15 °C (abs. zero) | −459.67 °F | 0 K |
| 180 °C (oven) | 356 °F |
| 200 °C (oven) | 392 °F |
Temperature Unit Definitions
- Celsius (°C)
- The SI-derived temperature scale where 0 °C = freezing water and 100 °C = boiling water at sea level.
- Fahrenheit (°F)
- Used mainly in the US. Water freezes at 32 °F and boils at 212 °F.
- Kelvin (K)
- The SI base unit of temperature. Starts at absolute zero (0 K = −273.15 °C). No degree symbol.
- Rankine (°R)
- Absolute temperature scale using Fahrenheit-sized degrees. 0 °R = absolute zero.
- Réaumur (°Ré)
- Historical scale where water freezes at 0 °Ré and boils at 80 °Ré.
Frequently Asked Questions
How do I convert Celsius to Fahrenheit?
Formula: °F = (°C × 9/5) + 32. Example: 25 °C → (25 × 1.8) + 32 = 77 °F.
How do I convert Fahrenheit to Celsius?
Formula: °C = (°F − 32) × 5/9. Example: 98.6 °F → (98.6 − 32) × 5/9 = 37 °C.
What is absolute zero?
Absolute zero is −273.15 °C or −459.67 °F (0 Kelvin). It is the lowest possible temperature — the point at which all molecular motion ceases.
Why does the US still use Fahrenheit?
The US uses the Fahrenheit scale as a historical convention. The scale was introduced in 1724 by Daniel Fahrenheit; metrication in the US never formally included temperature.