Fahrenheit to Kelvin Formula

The complete formula for converting fahrenheit (°F) to kelvin (K). See the formula, how it works, and worked examples below.

K = (°F - 32) × 5/9 + 273.15

How the Formula Works

Temperature conversion between fahrenheit and kelvin uses an offset formula, not a simple multiplication. This is because temperature scales have different zero points.

Worked Examples

0 °F to K

  1. Start with 0°F
  2. Convert to Celsius: (0 - 32) × 5/9 = -17.78°C
  3. Add 273.15: -17.78 + 273.15 = 255.37
  4. Result: 0°F = 255.37 K

20 °F to K

  1. Start with 20°F
  2. Convert to Celsius: (20 - 32) × 5/9 = -6.67°C
  3. Add 273.15: -6.67 + 273.15 = 266.48
  4. Result: 20°F = 266.48 K

37 °F to K

  1. Start with 37°F
  2. Convert to Celsius: (37 - 32) × 5/9 = 2.78°C
  3. Add 273.15: 2.78 + 273.15 = 275.93
  4. Result: 37°F = 275.93 K

100 °F to K

  1. Start with 100°F
  2. Convert to Celsius: (100 - 32) × 5/9 = 37.78°C
  3. Add 273.15: 37.78 + 273.15 = 310.93
  4. Result: 100°F = 310.93 K

200 °F to K

  1. Start with 200°F
  2. Convert to Celsius: (200 - 32) × 5/9 = 93.33°C
  3. Add 273.15: 93.33 + 273.15 = 366.48
  4. Result: 200°F = 366.48 K

Reverse Formula: Kelvin to Fahrenheit

°F = (K - 273.15) × 9/5 + 32

See the full Kelvin to Fahrenheit formula for worked examples.

Related

calculate Fahrenheit to Kelvin Converter swap_horiz Kelvin to Fahrenheit Converter thermostat Temperature Converter functions All Formulas

Frequently Asked Questions

The formula is: K = (°F - 32) × 5/9 + 273.15. See the worked examples above for step-by-step breakdowns, or use the Fahrenheit to Kelvin converter for instant results.
100 fahrenheit = 310.93 kelvin. Apply the formula: K = (°F - 32) × 5/9 + 273.15.
person Written by Sean Day verified Reviewed by UnitCompare update Last updated Mar 28, 2026