Fahrenheit to Celsius converter
This Fahrenheit to Celsius converter turns a temperature in °F into degrees Celsius as you type, for a US recipe, a meat thermometer, a fever reading or a thermostat set the American way.
Formula: °C = (°F − 32) ÷ 1.8 (100 − 32) ÷ 1.8 = 37.77777778
In every unit (4)
How the Fahrenheit to Celsius converter calculates
Type a value in degrees Fahrenheit and the Celsius figure shows up beside it, with Kelvin listed underneath. The page opens on 100 °F, which comes out at 37.78 °C, and readings below zero are fine: 0 °F is −17.78 °C. To work the other way, the round button takes you to the Celsius to Fahrenheit converter.
The °F to °C formula has two steps: take away 32, then divide by 1.8. For 100 °F, that is 68 ÷ 1.8 = 37.777…, which the Fahrenheit to Celsius converter rounds only on screen. The 1.8 comes from the size of the degrees: 180 Fahrenheit degrees separate the freezing point of water from its boiling point, against 100 Celsius degrees. NIST states it the same way: one Celsius degree spans 1.8 Fahrenheit degrees.
Common values
| °F | °C |
|---|---|
| -40 | -40 |
| 0 | -17.7778 |
| 10 | -12.2222 |
| 32 | 0 |
| 40 | 4.4444 |
| 50 | 10 |
| 60 | 15.5556 |
| 68 | 20 |
| 75 | 23.8889 |
| 85 | 29.4444 |
| 98.6 | 37 |
| 100 | 37.7778 |
| 212 | 100 |
| 325 | 162.7778 |
| 350 | 176.6667 |
| 400 | 204.4444 |
Fahrenheit to Celsius conversion in the kitchen and at home
A US recipe sets the oven in Fahrenheit. 375 °F is 190.6 °C and 425 °F is 218.3 °C; on a dial marked in Celsius, pick the nearest setting. Fan-assisted ovens and British gas marks are covered in our oven temperature conversion article. Candy and jam recipes work from 212 °F, the boiling point of water at sea level, which is exactly 100 °C.
USDA food safety charts are in Fahrenheit too: 165 °F for poultry (73.9 °C), 160 °F for ground beef (71.1 °C) and 145 °F for whole cuts of beef and pork (62.8 °C), followed by a three-minute rest. A meat thermometer bought in Europe reads Celsius, so run those numbers through the Fahrenheit to Celsius converter once and keep them on the fridge door.
For health, the CDC counts 100.4 °F as a fever, exactly 38 °C. At home, the Department of Energy suggests a summer thermostat setting of 78 °F, 25.6 °C, while you are in, and the Consumer Product Safety Commission advises keeping a hot tub at or below 104 °F, which is 40 °C.
Science classes and labs work in Celsius, so a US student who reads 72 °F on a classroom wall records 22.2 °C, a figure the Fahrenheit to Celsius converter gives at once. For a forecast, subtract 30 and halve: between 30 and 80 °F, the guess lands within 2 degrees of the true value.