Instant Unit Conversion
Convert Fahrenheit to Celsius (°F to °C)
Exact formula, conversion factors, live calculator, and reference charts for fahrenheit to celsius.
Method reviewed:Exact defined factors — international yard and pound (1959), US customary gallon and cup, SI — the values NIST SP 811 lists · reviewed September 2026
Direct AnswerFormula: °C = (°F − 32) × 5/9
To convert Fahrenheit to Celsius, subtract 32 from the Fahrenheit temperature and multiply by 5/9 (or divide by 1.8). For example, 68°F equals (68 − 32) / 1.8 = 20°C.
Live Fahrenheit to Celsius Calculator
Formula:
°C = (°F − 32) × 5/9Open full temperature converter →Fahrenheit to Celsius Conversion Table
Quick reference conversion chart from 1 to 100 fahrenheit.
| Fahrenheit (°F) | Celsius (°C) | Mathematical Formula |
|---|---|---|
| 1 °F | -17.2 °C | (1 − 32) × 5/9 |
| 2 °F | -16.7 °C | (2 − 32) × 5/9 |
| 5 °F | -15.0 °C | (5 − 32) × 5/9 |
| 10 °F | -12.2 °C | (10 − 32) × 5/9 |
| 15 °F | -9.4 °C | (15 − 32) × 5/9 |
| 20 °F | -6.7 °C | (20 − 32) × 5/9 |
| 25 °F | -3.9 °C | (25 − 32) × 5/9 |
| 50 °F | 10.0 °C | (50 − 32) × 5/9 |
| 75 °F | 23.9 °C | (75 − 32) × 5/9 |
| 100 °F | 37.8 °C | (100 − 32) × 5/9 |
Frequently Asked Questions
How do you convert °F to °C quickly?
Subtract 30 and divide by 2 for a fast mental approximation (e.g. 70°F − 30 = 40, / 2 = 20°C; exact is 21.1°C).