DailyCalc

Degrees Fahrenheit to Degrees Celsius (°F to °C)

°C = °F × 0.555556 − 17.77778. Type any value to convert it.

1 degree Fahrenheit =

-17.22222222 °C

degrees Celsius

Formula
°C = (°F − 32) ÷ 1.8

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Show in all common units
1 °F in other units
UnitValue
degree Celsius (°C)-17.22222222 °C
degree Fahrenheit (°F)1 °F
kelvin (K)255.9277778 K
degree Rankine (°R)460.67 °R

How to convert degrees Fahrenheit to degrees Celsius

°C = °F × 0.555556 − 17.77778

°C = (°F − 32) ÷ 1.8, exactly (NIST SP 811 B.9). Subtract 32 first, then divide; dividing first gives a wrong answer.

Examples

  • 100.4 °F = 38 °C: Reading above which MedlinePlus says a fever is likely (MedlinePlus (NIH))
  • 40 °F = 4.4444444 °C: FDA maximum refrigerator temperature (U.S. FDA)
  • 0 °F = -17.777778 °C: FDA recommended freezer temperature (U.S. FDA)

Fahrenheit to celsius chart

Degrees Fahrenheit to degrees Celsius
Degrees Fahrenheit (°F)Degrees Celsius (°C)
-40 °F-40 °C
0 °F-17.777778 °C
32 °F0 °C
40 °F4.4444444 °C
50 °F10 °C
68 °F20 °C
77 °F25 °C
98.6 °F37 °C
100.4 °F38 °C
212 °F100 °C
350 °F176.66667 °C
400 °F204.44444 °C
450 °F232.22222 °C

Common mistakes

  • Subtract before dividing: (68 − 32) ÷ 1.8 = 20, but 68 ÷ 1.8 − 32 is about 5.8.
  • For a temperature change, skip the 32: a rise of 9 °F is a rise of 5 °C.

Frequently asked questions

How do you convert Fahrenheit to Celsius?

Subtract 32, then divide by 1.8 (or multiply by 5/9). For 68 °F: 68 − 32 = 36, and 36 ÷ 1.8 = 20 °C.

What is 100.4 °F in Celsius?

100.4 °F is exactly 38 °C. MedlinePlus says a temperature over this most often means a fever.

What is 0 °F in Celsius?

0 °F is about −17.8 °C. The FDA rounds it to −18 °C when it gives the recommended freezer temperature.

Is 98.6 °F exactly 37 °C?

Yes, the conversion is exact. MedlinePlus adds that normal readings can range from 97 °F (36.1 °C) to 99 °F (37.2 °C).