How to Convert Fahrenheit to Celsius
Fahrenheit and Celsius are the two most common temperature scales used in daily life. The United States uses Fahrenheit for weather, cooking, and body temperature, while the rest of the world primarily uses Celsius. Knowing how to convert between them is essential for travel, cooking international recipes, and understanding weather forecasts.
The Conversion Formula
°C = (°F − 32) × 5/9
Or equivalently:
°C = (°F − 32) ÷ 1.8
Step-by-Step Example
Convert 98.6°F (normal body temperature) to Celsius:
- Subtract 32: 98.6 − 32 = 66.6
- Multiply by 5/9: 66.6 × 5 ÷ 9 = 37.0°C
Common Fahrenheit to Celsius Values
| Fahrenheit | Celsius | Context |
|---|---|---|
| 32°F | 0°C | Water freezes |
| 68°F | 20°C | Room temperature |
| 98.6°F | 37°C | Body temperature |
| 212°F | 100°C | Water boils |
| 350°F | 177°C | Baking oven |
| 425°F | 218°C | High-heat oven |
A Quick Mental Trick
For a rough mental estimate without a calculator:
- Subtract 30 from the Fahrenheit value
- Divide by 2
Example: 86°F → (86 − 30) ÷ 2 = 28°C (actual: 30°C). It's not exact, but useful for weather estimates.
Why Two Scales Exist
Gabriel Fahrenheit developed his scale in 1724, setting 0° at the coldest brine mixture he could create and 96° at human body temperature. Anders Celsius created his scale in 1742 with 0° at freezing water and 100° at boiling water—a more intuitive system that was adopted globally.
Use our Fahrenheit-to-Celsius calculator for exact, instant conversions.