Fahrenheit to Celsius
°C = (°F − 32) × 5/9
Convert Fahrenheit to Celsius with the reverse formula, everyday examples, and a free live converter.
How to convert Fahrenheit to Celsius
Subtract 32 from the Fahrenheit reading first. That removes the offset Fahrenheit uses so water freezes at 32°F instead of 0. Then multiply by 5/9 to shrink each Fahrenheit degree into a Celsius degree (180 Fahrenheit degrees fit into 100 Celsius degrees between freezing and boiling).
Worked example: convert 77°F to Celsius. First, 77 − 32 = 45. Then 45 × 5/9 = 25. So 77°F is 25°C — a warm, comfortable outdoor day in much of the world.
Weather shortcut many people use: a high of 50°F is about 10°C, 68°F is 20°C, and 86°F is 30°C. Those round numbers make US forecasts easier to remap onto metric intuition.
Common Fahrenheit to Celsius conversions
Useful landmarks for weather, cooking, and body temperature.
| Fahrenheit (°F) | Celsius (°C) | Notes |
|---|---|---|
| 32 | 0 | Freezing point of water |
| 68 | 20 | Mild room / outdoor |
| 98.6 | 37 | Approximate body temperature |
| 212 | 100 | Boiling point of water |
| −40 | −40 | Scales meet |
Body temperature and weather context
Clinical and popular references often cite 98.6°F as “normal” body temperature — about 37°C. Fever thresholds in °F (for example 100.4°F) land near 38°C. Always follow medical guidance for real health decisions. The conversion itself is just arithmetic: (100.4 − 32) × 5/9 ≈ 38°C.
For travel between the US and metric countries, anchoring on 32°F = 0°C keeps ice and frost forecasts comparable, while boiling recipes jump from 212°F recipes to 100°C labs and cookbooks.