100 °F to Celsius: 37.8 °C (+ Converter and Table)
I was watching a video that mentioned 100 degrees Fahrenheit, and immediately wondered: how much is that in Celsius, the scale we use?
The short answer: 100 °F = 37.78 °C, or about 37.8 °C — a mild fever in a person. Below are the formula, a converter and a table.
The conversion formula
To convert degrees Fahrenheit to degrees Celsius, subtract 32 from the temperature and multiply the result by 5/9:
°C = (°F − 32) × 5/9
For 100 °F: (100 − 32) × 5/9 = 68 × 5/9 ≈ 37.78 °C.
The other way round: °F = °C × 9/5 + 32. For example, 37 °C × 9/5 + 32 = 98.6 °F — the “normal body temperature” from American movies.
Temperature converter
Enter a number and press the button:
Google has a converter too — just type something like “100 F to C” into the search box:
Table: Fahrenheit → Celsius
| °F | °C | What it is |
|---|---|---|
| 0 | −17.8 | hard frost |
| 32 | 0 | water freezes |
| 50 | 10 | cool |
| 68 | 20 | room temperature |
| 86 | 30 | hot weather |
| 98.6 | 37 | normal body temperature |
| 100 | 37.8 | mild fever |
| 104 | 40 | high fever / extreme heat |
| 212 | 100 | water boils |
| 350 | 176.7 | oven in American recipes |
| 400 | 204.4 | hot oven |
Why Americans use Fahrenheit
Almost every country in the world measures temperature in Celsius; Fahrenheit has survived in the US and a few small countries, such as the Bahamas, the Cayman Islands and Palau.
The Celsius scale is logical: 0 degrees is the freezing point of water and 100 is its boiling point. On the Fahrenheit scale these points are 32 and 212 degrees.
A bit of history. Daniel Gabriel Fahrenheit proposed his scale in 1724, and Anders Celsius proposed his in 1742 — at first “upside down”: his 0 was the boiling point and 100 the freezing point; the scale got its familiar order after him.
In 1975 the US Congress passed the Metric Conversion Act to move to the metric system. A special body, the US Metric Board, was even set up, but the conversion was voluntary, with no deadlines or obligations, never fully happened, and the Board was dissolved in 1982.
I’m for a single system of measurement — the International System of Units (SI). It really is simpler and more universal!