18 °C at a glance
- Fahrenheit
- 64.4 °F
- Kelvin
- 291.15 K
- Rankine
- 524.07 °R
- Rounded
- 64 °F
- Quick estimate
- 66 °F
- As a change (Δ)
- Δ18 °C = Δ32.4 °F
How to convert 18 °C to Fahrenheit
18 × 1.8 = 32.4
32.4 + 32 = 64.4 °F
Multiply by 9/5 (1.8) because each Celsius degree spans 1.8 Fahrenheit degrees, then add 32 because water freezes at 32 °F rather than 0. The answer always has at most one decimal place, because multiplying a whole number by 1.8 can only leave tenths.
Estimate it in your head
Double it and add 30: 18 × 2 + 30 = 66 °F, which is 1.6 degrees high.
Careful with temperature changes: a rise of 18 °C is a rise of 32.4 °F — multiply by 1.8 but do not add 32.
18 °C outdoors and indoors
18 °C (64.4 °F) is fresh rather than warm: comfortable for brisk walking or running, but chilly for sitting still in the shade.
Indoors, 18 °C is cooler than most people like; the common winter thermostat setting of 20 °C (68 °F) is 2 degrees warmer.
Temperatures near 18 °C
| Celsius | Fahrenheit | Kelvin |
|---|---|---|
| 13 °C | 55.4 °F | 286.15 K |
| 14 °C | 57.2 °F | 287.15 K |
| 15 °C | 59 °F | 288.15 K |
| 16 °C | 60.8 °F | 289.15 K |
| 17 °C | 62.6 °F | 290.15 K |
| 18 °C | 64.4 °F | 291.15 K |
| 19 °C | 66.2 °F | 292.15 K |
| 20 °C | 68 °F | 293.15 K |
| 21 °C | 69.8 °F | 294.15 K |
| 22 °C | 71.6 °F | 295.15 K |
| 23 °C | 73.4 °F | 296.15 K |
Going the other way: 64 °F in Celsius is 17.78 °C.
Frequently asked questions
What is 18 °C in Fahrenheit?
18 °C is 64.4 °F: multiply by 1.8 (32.4) and add 32.
Is 18 °C hot or cold?
18 °C is cool to mild — light-jacket weather.
How do you convert 18 °C to Fahrenheit quickly?
Double it and add 30: 66 °F. The exact value is 64.4 °F.
What is 18 °C in Kelvin?
Add 273.15: 18 °C = 291.15 K.