0 °F = -17.7778 °C
Converting degrees Fahrenheit to degrees Celsius requires a temperature-scale formula, not just multiplication. For reference: 0 °F = -17.7778 °C, 20 °F = -6.66667 °C, 37 °F = 2.77778 °C, 100 °F = 37.7778 °C. Use the calculator below for any value, or scan the conversion table for common readings.
Degrees Celsius = Degrees Fahrenheit × 0.555556Begin with your temperature in degrees Fahrenheit.
°C = (°F − 32) × 5/9
The result is the equivalent temperature in degrees Celsius. For example, 100 °F = 37.7778 °C.
Temperature conversion is affine, not a single multiplication. The exact formula is shown below — it follows directly from the definitions of the degree Fahrenheit and degree Celsius scales.
°C = (°F − 32) × 5/9
Fifty common reference values, hand-picked for skim utility. Use the calculator above for any value not listed.
| Degrees Fahrenheit (°F) | Degrees Celsius (°C) |
|---|---|
| -50 °F | -45.556 °C |
| -40 °F | -40 °C |
| -30 °F | -34.444 °C |
| -25 °F | -31.667 °C |
| -20 °F | -28.889 °C |
| -15 °F | -26.111 °C |
| -10 °F | -23.333 °C |
| -5 °F | -20.556 °C |
| -2 °F | -18.889 °C |
| -1 °F | -18.333 °C |
| 0 °F | -17.778 °C |
| 1 °F | -17.222 °C |
| 2 °F | -16.667 °C |
| 5 °F | -15 °C |
| 10 °F | -12.222 °C |
| 15 °F | -9.4444 °C |
| 18 °F | -7.7778 °C |
| 20 °F | -6.6667 °C |
| 21 °F | -6.1111 °C |
| 22 °F | -5.5556 °C |
| 23 °F | -5 °C |
| 24 °F | -4.4444 °C |
| 25 °F | -3.8889 °C |
| 27 °F | -2.7778 °C |
| 28 °F | -2.2222 °C |
| 30 °F | -1.1111 °C |
| 32 °F | 0 °C |
| 35 °F | 1.6667 °C |
| 37 °F | 2.7778 °C |
| 40 °F | 4.4444 °C |
| 45 °F | 7.2222 °C |
| 50 °F | 10 °C |
| 55 °F | 12.778 °C |
| 60 °F | 15.556 °C |
| 65 °F | 18.333 °C |
| 70 °F | 21.111 °C |
| 75 °F | 23.889 °C |
| 80 °F | 26.667 °C |
| 85 °F | 29.444 °C |
| 90 °F | 32.222 °C |
| 95 °F | 35 °C |
| 100 °F | 37.778 °C |
| 110 °F | 43.333 °C |
| 120 °F | 48.889 °C |
| 150 °F | 65.556 °C |
| 180 °F | 82.222 °C |
| 200 °F | 93.333 °C |
| 250 °F | 121.11 °C |
| 300 °F | 148.89 °C |
| 500 °F | 260 °C |
Water freezes at 32 °F. Room temperature is around 68–72 °F. A hot summer day is around 90 °F.
The degree Fahrenheit (°F) is the customary temperature scale in the United States, defined since 1968 such that water freezes at exactly 32 °F and boils at exactly 212 °F at standard pressure — giving 180 Fahrenheit degrees over a range of 100 Celsius degrees. The scale was proposed in 1724 by Daniel Gabriel Fahrenheit, who calibrated zero against a brine ice bath. To convert °F to °C, subtract 32 then multiply by 5/9.
The degree Celsius (°C) is the SI-derived unit of temperature on a scale where 0 °C is the freezing point of water at standard pressure and 100 °C is the boiling point. Defined in 1742 by Anders Celsius (originally with the scale inverted) and refined repeatedly since, it shares its size of degree with the Kelvin: a change of 1 °C is identical to a change of 1 K. It is the everyday temperature unit almost everywhere outside the United States.