Temperature conversion
Fahrenheit to Celsius
One fahrenheit is -17.22222 degrees Celsius. Enter any value below to convert it instantly, or use the reference table further down for the numbers you need most often.
Conversion rate
1 °F = -17.22222 °C
°C = (°F − 32) × 5/9
1 °F = -17.22222 °C
Reference
Fahrenheit to Celsius table
The values people look up most often, rounded for practical use.
| Fahrenheit (°F) | Celsius (°C) | Written out |
|---|---|---|
| -40 °F | -40 °C | -40 degrees Fahrenheit = -40 degrees Celsius |
| -20 °F | -28.88889 °C | -20 degrees Fahrenheit = -28.88889 degrees Celsius |
| -10 °F | -23.33333 °C | -10 degrees Fahrenheit = -23.33333 degrees Celsius |
| 0 °F | -17.77778 °C | 0 degrees Fahrenheit = -17.77778 degrees Celsius |
| 10 °F | -12.22222 °C | 10 degrees Fahrenheit = -12.22222 degrees Celsius |
| 20 °F | -6.666667 °C | 20 degrees Fahrenheit = -6.666667 degrees Celsius |
| 25 °F | -3.888889 °C | 25 degrees Fahrenheit = -3.888889 degrees Celsius |
| 30 °F | -1.111111 °C | 30 degrees Fahrenheit = -1.111111 degrees Celsius |
| 37 °F | 2.777778 °C | 37 degrees Fahrenheit = 2.777778 degrees Celsius |
| 100 °F | 37.77778 °C | 100 degrees Fahrenheit = 37.77778 degrees Celsius |
How to convert degrees Fahrenheit to degrees Celsius
Temperature scales do not share a zero point, so you cannot convert them by multiplying alone — an offset is always involved. Apply °C = (°F − 32) × 5/9 and the result is exact.
Worked example: 12 degrees Fahrenheit × -17.22222 = -11.11111 degrees Celsius.
Where this conversion comes up
Temperature conversion matters most in cooking, weather and science. Two anchors are worth memorising: water freezes at 0 °C / 32 °F and boils at 100 °C / 212 °F. A rough mental shortcut for °C to °F is “double it and add 30”, which is close enough for weather but not for an oven.
Quick answers
- 1 fahrenheit = -17.22222 degrees Celsius
- 2 degrees Fahrenheit = -16.66667 degrees Celsius
- 5 degrees Fahrenheit = -15 degrees Celsius
- 10 degrees Fahrenheit = -12.22222 degrees Celsius
- 100 degrees Fahrenheit = 37.77778 degrees Celsius
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Answers
Frequently asked questions
°C = (°F − 32) × 5/9. The converter above applies it for you, but the formula is useful in a spreadsheet — put your value in column A and the formula in column B.Related tools
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