−40 °F to °C
−40 °F = −40 °C
−40 degrees Fahrenheit is −40 °C. In Kelvin that is 233.15 K. This is the one temperature where Celsius and Fahrenheit read the same number.
The working
°C = (°F − 32) × 5/9
- −40 − 32 = −72
- −72 × 5/9 = −40
Convert a different value
°F
°C
K
°R