100 degrees Fahrenheit to degrees Celsius
100 degrees Fahrenheit = 37.7778 degrees Celsius
Formula: degrees Celsius = (degrees Fahrenheit - 32) x 5/9
One hundred degrees Fahrenheit is a hot day and close to a feverish body temperature, and its Celsius value is how that heat is described internationally.
How to Convert degrees Fahrenheit to degrees Celsius
Fahrenheit converts to Celsius with an affine formula because the scales have different zero points. You subtract 32 from the Fahrenheit value and then multiply by 5/9. The scales coincide only at minus forty degrees, where both read the same number.
The formula is degrees Celsius = (degrees Fahrenheit - 32) x 5/9. Apply the formula to 100 degrees Fahrenheit: 100 - 32 = 68, then 68 x 5/9 = 37.7778 degrees Celsius.
The reverse is just as direct: 37.7778 degrees Celsius equals 100 degrees Fahrenheit. That symmetry is a quick way to sanity-check any conversion you make.
degrees Fahrenheit to degrees Celsius Conversion Table
Use this table to read off nearby values at a glance. The highlighted row is the 100-degrees Fahrenheit conversion from this page.
| degrees Fahrenheit | degrees Celsius |
|---|---|
| 0 | -17.7778 |
| 10 | -12.2222 |
| 20 | -6.6667 |
| 30 | -1.1111 |
| 40 | 4.4444 |
| 50 | 10 |
| 60 | 15.5556 |
| 70 | 21.1111 |
| 80 | 26.6667 |
| 90 | 32.2222 |
| 100 | 37.7778 |
Reverse: degrees Celsius to degrees Fahrenheit
Need to go the other way? 37.7778 degrees Celsius converts back to 100 degrees Fahrenheit. For the full breakdown in that direction, see 100 degrees Celsius to degrees Fahrenheit.
Frequently Asked Questions
How do I convert 100 degrees Fahrenheit to degrees Celsius?
100 degrees Fahrenheit equals 37.7778 degrees Celsius. You subtract 32 and multiply by 5/9 to get there, because the two scales start from different zero points and so are not simply proportional.
Why can't I just multiply to convert temperature?
Because the scales are offset, not just stretched. Each has a different zero, so you must scale and then shift. The single point where both scales show the same number is minus forty degrees, a useful sanity check.
How do I convert 37.7778 degrees Celsius back to degrees Fahrenheit?
Reversing the formula returns 100 degrees Fahrenheit, your starting temperature. The unit conversion calculator linked below handles any Celsius or Fahrenheit value.
Convert Any Value
Need a different number or unit? Open the Unit Conversion Calculator to convert temperature between any units instantly.
Open the Unit Conversion CalculatorBrowse all unit conversions or open the Unit Conversion Calculator.
Disclaimer: This calculator is for informational and educational purposes only. Results are estimates and may not reflect exact values.
Last updated: June 13, 2026