How to convert degrees Fahrenheit to degrees Celsius
Temperature scales have different zero points, so the conversion multiplies and then adds an offset:
°C = °F × 0.555556 − 17.7778
°F = (°C + 17.7778) ÷ 0.555556
Example: 32 °F → 32 × 0.555556 − 17.7778 = 0 °C.
To convert the other way, use the degrees Celsius to degrees Fahrenheit converter.
Everyday values
| Degrees Fahrenheit | Degrees Celsius | For example |
|---|---|---|
| 32 °F | 0 °C | water freezes |
| 68 °F | 20 °C | room temperature |
| 98.6 °F | 37 °C | normal body temperature |
| 100.4 °F | 38 °C | fever threshold often used |
| 212 °F | 100 °C | water boils |
| 350 °F | 176.667 °C | a moderate oven |
When you need this conversion
The quick reverse estimate is "subtract 30 and halve": 80 °F → 25 °C (exact: 26.7 °C). Body temperature of 98.6 °F is 37 °C, and a reading of 100.4 °F (38 °C) or higher is commonly treated as a fever.
Degree Fahrenheit to degree Celsius conversion table
| °F | °C | °F | °C |
|---|---|---|---|
| 0 °F | -17.7778 °C | 130 °F | 54.4444 °C |
| 10 °F | -12.2222 °C | 140 °F | 60 °C |
| 20 °F | -6.6667 °C | 150 °F | 65.5556 °C |
| 30 °F | -1.1111 °C | 160 °F | 71.1111 °C |
| 40 °F | 4.4444 °C | 170 °F | 76.6667 °C |
| 50 °F | 10 °C | 180 °F | 82.2222 °C |
| 60 °F | 15.5556 °C | 190 °F | 87.7778 °C |
| 70 °F | 21.1111 °C | 200 °F | 93.3333 °C |
| 80 °F | 26.6667 °C | 210 °F | 98.8889 °C |
| 90 °F | 32.2222 °C | 220 °F | 104.444 °C |
| 100 °F | 37.7778 °C | 230 °F | 110 °C |
| 110 °F | 43.3333 °C | 240 °F | 115.556 °C |
| 120 °F | 48.8889 °C |
About the units
- Degree Fahrenheit (°F): a scale on which water freezes at 32° and boils at 212° at sea level.
- Degree Celsius (°C): the kelvin scale shifted by 273.15.
Both are units of temperature. The conversion factor comes from the exact definitions above.
Frequently asked questions
What is the formula for degrees Fahrenheit to degrees Celsius?
°C = °F × 0.555556 − 17.7778. For example, 32 °F is 0 °C.
How do I convert degrees Fahrenheit to degrees Celsius?
Use °C = °F × 0.555556 − 17.7778.
What is 32 °F in degrees Celsius?
32 °F = 0 °C.
What is 68 °F in degrees Celsius?
68 °F = 20 °C.
Sources
- NIST Special Publication 811 (2008), Guide for the Use of the International System of Units (SI), Appendix B: conversion factors.
- NIST Handbook 44 (2024), Appendix C: General tables of units of measurement.
Last reviewed 5 October 2026. Results are estimates; see our disclaimer.