At One Place

21 K to °F

21 kelvin in degrees Fahrenheit
21 K = -421.87 °F
°F = K × 9/5 − 459.67

21 kelvin is -421.87 degrees Fahrenheit. To get there, use °F = K × 9/5 − 459.67.

Values either side

Kelvin near 21, converted to degrees Fahrenheit.
Kelvin Degrees Fahrenheit
17 K -429.07
18 K -427.27
19 K -425.47
20 K -423.67
21 K ← -421.87
22 K -420.07
23 K -418.27
24 K -416.47
25 K -414.67

How the conversion works

The relationship is °F = K × 9/5 − 459.67. Both units measure temperature, so the conversion is a fixed formula that never changes. Temperature scales are the one common case where converting is not just multiplication — Celsius and Fahrenheit each put their zero in a different place, so an offset is applied as well as a scale factor.

Common questions

What is 21 K in degrees Fahrenheit?
21 K is -421.87 °F.
How do you convert kelvin to degrees Fahrenheit?
Use °F = K × 9/5 − 459.67.

Related pages

Sources

  1. Guide for the Use of the International System of Units (SP 811) — NIST (Public domain (US Government))
  2. The International System of Units (SI Brochure) — Bureau International des Poids et Mesures
  3. Calculated on this page — At One Place

How these figures are compiled and checked