Temperature

21 °F in Celsius

Quick answer, the exact math, and nearby values. Need a different number? Use the Fahrenheit to Celsius Converter - Free.

How to convert it

Subtract 32: 21 − 32 = -11.
Multiply by 5/9: -11 × 5 ÷ 9 = -6.11 °C.

C = (F - 32) x 5/9

That is below the freezing point of water (0 °C / 32 °F), so expect ice and frost.

Convert another value →

Nearby values

Value	Result
15 °F in Celsius	15 °F = -9.4 °C
16 °F in Celsius	16 °F = -8.9 °C
17 °F in Celsius	17 °F = -8.3 °C
18 °F in Celsius	18 °F = -7.8 °C
19 °F in Celsius	19 °F = -7.2 °C
20 °F in Celsius	20 °F = -6.7 °C
21 °F in Celsius	21 °F = -6.1 °C
22 °F in Celsius	22 °F = -5.6 °C
23 °F in Celsius	23 °F = -5 °C
24 °F in Celsius	24 °F = -4.4 °C
25 °F in Celsius	25 °F = -3.9 °C
26 °F in Celsius	26 °F = -3.3 °C
27 °F in Celsius	27 °F = -2.8 °C

Frequently asked questions

What is 21 °F in Celsius?

21 °F = -6.1 °C (about -6 °C).

How is it calculated?

Subtract 32: 21 − 32 = -11. Multiply by 5/9: -11 × 5 ÷ 9 = -6.11 °C.

Conversion factors follow: NIST Special Publication 811 — Guide for the Use of the International System of Units (SI); BIPM — The International System of Units (SI Brochure, 9th edition).