Where do these numbers come from?
- NISTSP 811 exact unit definitions (1 in = 25.4 mm, 1 lb = 453.59237 g)current edition
- NISTHandbook 44, weights and measurescurrent edition
- King Arthur BakingIngredient Weight Chart (kitchen tools)retrieved Oct 23, 2026
Checked Oct 23, 2026. °F = °C × 9/5 + 32, so 180 °C = 356 °F; ovens usually round this to 350 °F.
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-40 °C = -40 °F
Worked example
-40 × 9/5 = -72; -72 + 32 = -40 °F.
−40 is the one point where Celsius and Fahrenheit read the same. This is below the freezing point of water (0 °C / 32 °F).
Nearby values
| Celsius | Fahrenheit |
|---|---|
| -50 °C | -58 °F |
| -48 °C | -54.4 °F |
| -46 °C | -50.8 °F |
| -44 °C | -47.2 °F |
| -42 °C | -43.6 °F |
| -40 °C | -40 °F |
| -38 °C | -36.4 °F |
| -36 °C | -32.8 °F |
| -34 °C | -29.2 °F |
| -32 °C | -25.6 °F |
| -30 °C | -22 °F |
Related
Frequently asked questions
What is -40 °C in Fahrenheit?
-40 °F.
Is -40 °C hot or cold?
−40 is the one point where Celsius and Fahrenheit read the same. This is below the freezing point of water (0 °C / 32 °F).