How to convert fahrenheit to celsius

Step-by-step explanation of how to convert fahrenheit to celsius, with formulas, worked examples, and a free online calculator.

To convert Fahrenheit to Celsius, subtract 32 then multiply by 5/9. The formula is: C = (F − 32) × 5/9. Quick reference points: 32°F = 0°C (freezing point of water), 70°F ≈ 21°C (room temperature), 98.6°F = 37°C (body temperature), 212°F = 100°C (boiling point of water). For a fast mental estimate: subtract 30, then halve. For example, 80°F: 80 − 30 = 50, then 50 ÷ 2 = 25°C (actual: 26.7°C). The estimate gets you close enough for most everyday use.