The Fahrenheit to Celsius formula
To convert Fahrenheit to Celsius, subtract 32 then multiply by 5/9: °C = (°F − 32) × 5/9. For example, (98.6 − 32) × 5/9 = 37 °C, normal body temperature. To go back, use the Celsius to Fahrenheit calculator.
A second worked example for the oven: 350 °F is a common baking temperature, and (350 − 32) × 5/9 = 176.7 °C, which recipes normally round to 180 °C. Going the other way, 200 °C is 392 °F, usually written as 390 °F or 400 °F on a dial.
How to convert °F to °C
Enter a temperature in Fahrenheit and the calculator subtracts 32 and multiplies by 5/9 to give Celsius. Use it for weather, recipes, and health. Negative results are fine — −40 °F equals −40 °C.
For a quick mental estimate, subtract 30 and halve: 70 °F becomes about 20 °C, against a true value of 21.1 °C. The shortcut is close enough for weather but drifts at the extremes, so use the exact formula for cooking, medicine or lab work.
Useful anchors worth memorising: 0 °F is −17.8 °C, 50 °F is 10 °C, 68 °F is 20 °C (standard room temperature), 86 °F is 30 °C, and 104 °F is 40 °C — the point at which a fever becomes a medical emergency. Note that −40 is the single temperature where both scales agree.
The kelvin to celsius calculator answers the question that usually follows this one.
Fahrenheit to Celsius reference table
| Fahrenheit | Celsius |
|---|---|
| 32 °F | 0 °C |
| 98.6 °F | 37 °C |
| 212 °F | 100 °C |
| −40 °F | −40 °C |
Many people follow this up with the fahrenheit to kelvin calculator.
Frequently asked questions
- What is 98.6 Fahrenheit in Celsius?
- 98.6 °F equals 37 °C ((98.6 − 32) × 5/9).
- What is the Fahrenheit to Celsius formula?
- °C = (°F − 32) × 5/9.
- What is freezing point in Celsius?
- Water freezes at 32 °F, which is 0 °C.
- How do I convert Celsius back to Fahrenheit?
- Multiply by 9/5 and add 32, or use the Celsius to Fahrenheit calculator.
- Why can I not just multiply by 5/9 and skip the 32?
- Because the two scales have different zero points as well as different degree sizes. Water freezes at 32 °F but 0 °C, so the 32 must come off first — skipping it turns 50 °F into 27.8 °C instead of the correct 10 °C.