°F to °C conversion formula
Fahrenheit (°F) is the temperature scale used in the United States, where water freezes at 32° and boils at 212°.
Celsius (°C) is the metric temperature scale where water freezes at 0° and boils at 100° (at sea-level pressure). Standard across most of the world.
°F to °C conversion table
| °F | °C |
|---|---|
| 0 °F | -17.7778 °C |
| 10 °F | -12.2222 °C |
| 20 °F | -6.6667 °C |
| 30 °F | -1.1111 °C |
| 40 °F | 4.4444 °C |
| 50 °F | 10 °C |
| 60 °F | 15.5556 °C |
| 70 °F | 21.1111 °C |
| 80 °F | 26.6667 °C |
| 90 °F | 32.2222 °C |
| 100 °F | 37.7778 °C |
How to convert °F to °C
- Write down the value in °F you want to convert.
- Apply the formula: °C = (°F − 32) × 5⁄9.
- Read your result in °C. Done.
Real-world examples
- A US oven set to 350 °F is 177 °C — the universal “moderate” baking temperature.
- Normal body temperature, 98.6 °F, is 37 °C — the number every thermometer in the world shows.
- A hot summer day at 95 °F is 35 °C; the fever threshold of 100.4 °F is exactly 38 °C.
- −40° is the famous crossover point: −40 °F = −40 °C, the only temperature identical on both scales.
Common mistakes
The most common slip is applying the 5/9 ratio without removing 32 first: 80 °F is not 44 °C but 26.7 °C, because the Fahrenheit scale starts at 32 for freezing, not 0. Second trap: weather vs oven context — 200 °F is a warm summer record, but as an oven temperature it's barely warm; ovens run 300–500 °F. Always read the number in its context before converting.
Quick mental conversion
For weather temperatures, the 30 rule is fast enough: subtract 30, then halve. 72 °F → 42 → 21 °C (exact: 22.2). It fails for extreme values, but for the 30–100 °F range it's never off by more than 2 degrees — enough to dress correctly. Reverse (C to F): double and add 30. 25 °C → 50 + 30 = 80 °F (exact: 77 — close enough for packing a suitcase).
Frequently asked questions
How many °C is 1 °F?
Using the official conversion factor, 1 degree Fahrenheit = -17.2222 degree Celsius. The converter above handles any value instantly.
What is the formula to convert degree Fahrenheit to degree Celsius?
°C = (°F − 32) × 5⁄9. Apply it directly, or simply use the converter above.
Is this °F to °C converter free?
Yes — 100% free, unlimited, with no sign-up. CalculUnits is funded by non-intrusive ads, never by paywalls.