Convert 100°F to Celsius
Temperature converter
100°F equals
37.78°C
Very hot: Heatwave or hotter
How to convert 100°F to °C
Follow these steps to check the answer yourself.
- 1
Write the conversion formula
To convert Fahrenheit to Celsius, subtract 32 and multiply by 5/9.
°C = (°F − 32) × 5/9
- 2
Substitute the Fahrenheit value
Replace °F with 100.
°C = (100 − 32) × 5/9
- 3
Subtract 32
Work out the bracket first.
100 − 32 = 68
- 4
Multiply by 5/9
Scale the result to Celsius.
68 × 5/9 = 37.78
Answer: 100°F = 37.78°C
100°F and nearby temperatures
Fahrenheit values from 95°F to 105°F converted to Celsius and Kelvin. Select a value to open its own conversion page.
| Fahrenheit | Celsius | Kelvin |
|---|---|---|
| 95°F to °C | 35°C | 308.15 K |
| 96°F to °C | 35.56°C | 308.71 K |
| 97°F to °C | 36.11°C | 309.26 K |
| 98°F to °C | 36.67°C | 309.82 K |
| 99°F to °C | 37.22°C | 310.37 K |
| 100°F (this page) | 37.78°C | 310.93 K |
| 101°F to °C | 38.33°C | 311.48 K |
| 102°F to °C | 38.89°C | 312.04 K |
| 103°F to °C | 39.44°C | 312.59 K |
| 104°F to °C | 40°C | 313.15 K |
| 105°F to °C | 40.56°C | 313.71 K |
Fahrenheit to Celsius conversion chart
Common temperatures from -40°F to 450°F. Bookmark or print this chart for quick reference.
| °F | °C |
|---|---|
| -40°F | -40°C |
| -20°F | -28.89°C |
| 0°F | -17.78°C |
| 10°F | -12.22°C |
| 20°F | -6.67°C |
| 32°F | 0°C |
| 40°F | 4.44°C |
| 50°F | 10°C |
| °F | °C |
|---|---|
| 60°F | 15.56°C |
| 70°F | 21.11°C |
| 80°F | 26.67°C |
| 90°F | 32.22°C |
| 98.6°F | 37°C |
| 100°F | 37.78°C |
| 110°F | 43.33°C |
| 120°F | 48.89°C |
| °F | °C |
|---|---|
| 150°F | 65.56°C |
| 200°F | 93.33°C |
| 212°F | 100°C |
| 250°F | 121.11°C |
| 300°F | 148.89°C |
| 350°F | 176.67°C |
| 400°F | 204.44°C |
| 450°F | 232.22°C |
Is 100°F hot or cold?
100°F (37.78°C) reads as very hot on the thermometer: heatwave or hotter. Typical context: hot weather and human body temperature range.
100°F is 1.4°F warmer than average human body temperature (98.6°F), and 34.06°F cooler than the hottest air temperature ever recorded (Death Valley, California, 1913) (134.06°F).
Medical reference: 37.8°C is within the range of typical body temperatures, which vary between people and through the day.
Quick mental math
To estimate Fahrenheit to Celsius in your head, subtract 30 from the Fahrenheit value and halve it.
(100 − 30) ÷ 2 = 35°C (exact answer: 37.78°C)
The shortcut is close for everyday temperatures but drifts further from the exact answer in very hot or very cold conditions.
To go the other way, use the Celsius to Fahrenheit converter: 37.78°C converts back to 100°F.
Frequently asked questions
What is 100°F in Celsius?
100°F equals 37.78°C. This is calculated with the standard Fahrenheit to Celsius formula.
How do I convert 100 Fahrenheit to Celsius?
To convert Fahrenheit to Celsius, subtract 32 and multiply by 5/9. For 100°F the result is 37.78°C.
Is 100°F hot or cold?
37.8°C is very hot - dangerously high for prolonged exposure. Heat precautions needed.
What is the formula for Fahrenheit to Celsius conversion?
The formula is: °C = (°F − 32) × 5/9
Is 100°F a normal body temperature?
37.8°C is within the range of typical body temperatures, which vary between people and through the day.
Good to know
- Anders Celsius proposed his scale in 1742. It was originally inverted, with 0 for boiling water and 100 for freezing; the order was flipped soon after his death.
- Daniel Gabriel Fahrenheit introduced his scale in 1724. The United States and a handful of other countries still use it for everyday temperatures.
- -40 is the only temperature that reads the same in Celsius and Fahrenheit.
- A change of 1°C or 1 K equals a change of 1.8°F.
Sources
- SI Units – Temperature (NIST (US National Institute of Standards and Technology))
Conversion formulas between °C, °F and K, and the 273.15 offset.
- High temperature (fever) in adults (NHS)
A high temperature is usually considered to be 38°C or above.
Written and checked by Abdul Manan.
Last updated . Results are for general information; see the disclaimer.