18 Celsius to Fahrenheit
18°C = 64.4°F
18 degrees Celsius is equal to 64.4 degrees Fahrenheit.
Convert 18 Celsius to Fahrenheit using our free temperature converter.
How to convert 18 °C to °F
Use the formula °F = (°C × 9/5) + 32 and substitute 18 for °C:
°F = (18 × 9/5) + 32°F = 32.4 + 32°F = 64.4
So 18 °C = 64.4 °F.
What does 18 °C mean?
18 °C is mild. It is pleasant for being active outdoors, and slightly below what most people consider a comfortable indoor temperature.
- Fahrenheit
- 64.4 °F
- Kelvin
- 291.15 K
- Quick estimate (double + 30)
- 66 °F
For 18 °C the quick “double it and add 30” estimate gives 66 °F — 1.6 °F too high. The shortcut works best between about 0 °C and 20 °C; use the exact formula for anything that matters.
More in this range: Weather & room temperature (0–34 °C).
18 °C and nearby values
Related conversions
The Celsius to Fahrenheit formula
°F = (°C × 9/5) + 32
Multiply the Celsius temperature by 9/5 (1.8) because a Celsius degree is 1.8 times larger than a Fahrenheit degree, then add 32 because water freezes at 32 °F rather than 0 °F. To go the other way, use °C = (°F − 32) × 5/9 — for example, 64.4 °F back to Celsius gives 18 °C.
See the formula explained in detail or the step-by-step conversion guide.
Frequently asked questions
What is 18 Celsius in Fahrenheit?
18 degrees Celsius is equal to 64.4 degrees Fahrenheit (18 °C = 64.4 °F).
How do you convert 18 °C to °F?
Multiply 18 by 9/5 (or 1.8) and add 32: (18 × 1.8) + 32 = 64.4 °F.
Is 18 °C hot or cold?
It is mild — neither hot nor cold. 18 °C is 64.4 °F.
What is 18 °C in Kelvin?
Add 273.15 to the Celsius value: 18 °C = 291.15 K.