15 °F at a glance
- Celsius
- −9.44 °C
- Exact fraction
- −9 4/9 °C
- Kelvin
- 263.71 K
- Rankine
- 474.67 °R
- Rounded
- −9 °C
- Quick estimate
- −7.5 °C
How to convert 15 °F to Celsius
(15 − 32) × 5/9 = −17 × 5/9 = −85/9 = −9.44 °C
Subtract 32 first because the two scales put zero in different places, then multiply by 5/9 because a Fahrenheit degree is only 5/9 the size of a Celsius degree. −17 is not a multiple of 9, so the exact answer is the repeating decimal −9 4/9 °C.
Estimate it in your head
Subtract 30 and halve: (15 − 30) ÷ 2 = −7.5 °C. That is 1.9 degrees high, close enough to decide what to wear.
What 15 °F means in everyday life
- Freezers. Home freezers should hold 0 °F (−17.8 °C), so 15 °F is 15 degrees warmer than a properly set freezer — still cold enough to keep ice solid.
- Ice. At −9.44 °C, puddles, ponds and wet roads freeze. Rock salt melts ice well near 32 °F but works more and more slowly as pavement temperatures drop into the teens and below.
- Wind chill. With wind, 15 °F feels much colder:
| Wind | Feels like | In °C | Note |
|---|---|---|---|
| 10 mph | 3 °F | −16 °C | Dress in layers |
| 20 mph | −2 °F | −19 °C | Cover exposed skin |
| 30 mph | −5 °F | −21 °C | Cover exposed skin |
Temperatures near 15 °F
| Fahrenheit | Celsius | Kelvin |
|---|---|---|
| 10 °F | −12.22 °C | 260.93 K |
| 11 °F | −11.67 °C | 261.48 K |
| 12 °F | −11.11 °C | 262.04 K |
| 13 °F | −10.56 °C | 262.59 K |
| 14 °F | −10 °C | 263.15 K |
| 15 °F | −9.44 °C | 263.71 K |
| 16 °F | −8.89 °C | 264.26 K |
| 17 °F | −8.33 °C | 264.82 K |
| 18 °F | −7.78 °C | 265.37 K |
| 19 °F | −7.22 °C | 265.93 K |
| 20 °F | −6.67 °C | 266.48 K |
Going the other way: −9 °C in Fahrenheit is 15.8 °F.
Frequently asked questions
What is 15 °F in Celsius?
15 °F is −9.44 °C: subtract 32 (−17) and multiply by 5/9.
Is 15 °F hot or cold?
15 °F is below freezing — water turns to ice and roads can be slick.
How do you convert 15 °F to Celsius in your head?
Subtract 30 and divide by 2: (15 − 30) ÷ 2 = −7.5 °C, compared with the exact −9.44 °C.
What is 15 °F in Kelvin?
15 °F is 263.71 K. Convert to Celsius (−9.44 °C) and add 273.15.