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