-18 Fahrenheit to Celsius
-18 degrees Fahrenheit equals
-27.78°C
-27.78 degrees Celsius
-18°F is -27.78°C, well below the point where water freezes. Roads ice over here, and this is where winter forecasts in northern climates spend most of the season. For reference, water freezes at 0°C, or 32°F.
How to convert -18°F to °C
Formula
°C = (°F − 32) × 5/9
Substituting -18°F
- -18 − 32 = -50
- -50 × 5/9 = -27.78
Fahrenheit places the freezing point of water at 32 rather than 0, so that offset comes off first. What remains is then scaled by 5/9, because a Celsius degree covers 1.8 times as much temperature change as a Fahrenheit degree.
How -18°F compares
| Reference point | Temperature | Difference |
|---|---|---|
| Freezing point of water | 0°C / 32°F | 27.8°C (50°F) colder |
| Room temperature | 21°C / 69.8°F | 48.8°C (87.8°F) colder |
| Body temperature | 37°C / 98.6°F | 64.8°C (116.6°F) colder |
| Boiling point of water | 100°C / 212°F | 127.8°C (230°F) colder |