15 °F to °C

15 °F equals −9.44 °C. 15 °F is below freezing — water turns to ice and roads can be slick.

Negative values are fine down to absolute zero (−459.67 °F).
Formula
°C = (°F − 32) × 5/9
Kelvin
263.71 K
Rankine
474.67 °R
As a temperature change
Δ15 °F = Δ8.3333 °C
15 °F =−9.44 °C−9.4444 degrees Celsius

Show the work

  1. °C = (°F − 32) × 5/9
  2. Subtract 32: 15 − 32 = −17
  3. Multiply by 5/9 (divide by 1.8): −17 × 5/9 = −9.4444 °C
Fahrenheit to Celsius conversion table
°F°CReference point
−40−40Both scales read the same
−20−28.89
0−17.78Freezer setting
10−12.22
20−6.67
320Water freezes
404.44Refrigerator limit
5010
6015.56
6518.33
6820Room temperature
7021.11
7222.22
7523.89
8026.67
8529.44
9032.22
9535
9736.11
9836.67
98.637Traditional normal body temp
9937.22
10037.78
100.438Fever threshold
10138.33
10238.89
10339.44
10440High fever
11043.33
12048.89
14562.78Whole cuts of beef, pork (USDA)
16071.11Ground meat (USDA)
16573.89Poultry (USDA)
212100Water boils at sea level
250121.11
300148.89
325162.78
350176.67Moderate oven
375190.56
400204.44
425218.33
450232.22
500260

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

°C = (°F − 32) × 5/9
(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:
WindFeels likeIn °CNote
10 mph3 °F−16 °CDress in layers
20 mph−2 °F−19 °CCover exposed skin
30 mph−5 °F−21 °CCover exposed skin

Temperatures near 15 °F

FahrenheitCelsiusKelvin
10 °F−12.22 °C260.93 K
11 °F−11.67 °C261.48 K
12 °F−11.11 °C262.04 K
13 °F−10.56 °C262.59 K
14 °F−10 °C263.15 K
15 °F−9.44 °C263.71 K
16 °F−8.89 °C264.26 K
17 °F−8.33 °C264.82 K
18 °F−7.78 °C265.37 K
19 °F−7.22 °C265.93 K
20 °F−6.67 °C266.48 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.

Need a different value? Use the Fahrenheit to Celsius converter, or browse the Fahrenheit to Celsius chart.

Sources: Wind chill and heat index use the US National Weather Service formulas. Health and food-safety thresholds are from the CDC, FDA, USDA, CPSC and US Department of Energy.