To convert Fahrenheit to Celsius, subtract 32 then multiply by 5/9. Formula: °C = (°F − 32) × 5/9. Key values: 32°F = 0°C, 72°F = 22.2°C, 98.6°F = 37°C, 212°F = 100°C. Quick mental estimate: subtract 30 and halve.
- Formula: °C = (°F − 32) × 5/9 (subtracting 32 removes the zero offset; multiplying by 5/9 scales to Celsius degree size).
- 98.6°F = 37°C - normal human body temperature.
- 350°F = 176.7°C - common moderate oven temperature in US recipes.
- 32°F = 0°C - water freezes; 212°F = 100°C - water boils at sea level.
How to Use This Converter
Type any Fahrenheit value in the °F field and the Celsius result appears instantly. You can also type in the °C field to convert back to Fahrenheit - it works in both directions without pressing a button.
How Do You Convert Fahrenheit to Celsius?
Subtract 32 first to remove the zero-point offset, then multiply by 5/9 to scale from Fahrenheit degree size to Celsius degree size. The two-step process is necessary because the scales differ in both where zero is and how large each degree is.
$$°C = (°F - 32) \times \frac{5}{9}$$
Worked examples: 32°F = 0°C. 68°F = 20°C. 72°F = 22.2°C. 98.6°F = 37°C. 212°F = 100°C. 350°F = 176.7°C. 400°F = 204.4°C.
Mental shortcut: subtract 30 and halve. For 72°F: 72 − 30 = 42, ÷ 2 = 21°C (actual: 22.2°C, error ~1°C). Works well for everyday weather and room temperatures but loses accuracy at extremes.
How Do You Convert Celsius to Fahrenheit?
Multiply by 9/5 then add 32. See the dedicated Celsius to Fahrenheit converter for a Celsius-first reference table.
$$°F = °C \times \frac{9}{5} + 32$$
Worked examples: 0°C = 32°F. 20°C = 68°F. 37°C = 98.6°F. 100°C = 212°F.
Fahrenheit to Celsius Reference Table
Common US temperatures converted using the exact formula °C = (°F − 32) × 5/9:
| Fahrenheit (°F) | Celsius (°C) | Context |
|---|---|---|
| -40°F | -40°C | Scales are equal at this point |
| 0°F | -17.8°C | Very cold; Fahrenheit zero |
| 32°F | 0°C | Water freezes |
| 50°F | 10°C | Cool day |
| 68°F | 20°C | Comfortable room temperature |
| 72°F | 22.2°C | Typical US indoor thermostat |
| 86°F | 30°C | Hot day |
| 98.6°F | 37°C | Normal body temperature |
| 100.4°F | 38°C | Fever threshold (adults) |
| 212°F | 100°C | Water boils at sea level |
| 325°F | 162.8°C | Slow oven |
| 350°F | 176.7°C | Moderate oven (most baking) |
| 400°F | 204.4°C | Hot oven |
| 450°F | 232.2°C | Very hot oven / pizza |
When Do You Need to Convert Fahrenheit to Celsius?
The Fahrenheit scale is used in the US for everyday temperatures. Everyone else uses Celsius. Common conversion needs:
- Cooking - US recipes give oven temperatures in °F. Converting to °C (or gas marks) is needed for European ovens and most non-US recipe websites.
- Weather - US weather forecasts in °F need converting for travellers and people moving from metric countries.
- Medicine - US thermometers and medical references use °F. 98.6°F = 37°C (normal); 100.4°F = 38°C (fever).
- HVAC - US air conditioning and heating settings are in °F; international equipment and standards use °C.
Frequently Asked Questions
How do you convert Fahrenheit to Celsius?
Subtract 32, then multiply by 5/9. Formula: °C = (°F − 32) × 5/9. Example: 98.6°F − 32 = 66.6, × 5/9 = 37°C. Quick mental estimate: subtract 30, then halve (works within 2–3°C for everyday temps).
What is 72°F in Celsius?
72°F = 22.2°C. Calculation: (72 − 32) × 5/9 = 40 × 5/9 = 22.22°C. This is a common comfortable indoor temperature.
What is 350°F in Celsius?
350°F = 176.7°C. Calculation: (350 − 32) × 5/9 = 318 × 5/9 = 176.67°C. This is the most common oven temperature in US baking recipes.
What is 100°F in Celsius?
100°F = 37.8°C. Calculation: (100 − 32) × 5/9 = 68 × 5/9 = 37.78°C. This is just above normal body temperature (37°C) and approaches the fever threshold (38°C / 100.4°F).