Fahrenheit to Kelvin Converter – °F to K
Convert Fahrenheit to kelvin with K = (°F + 459.67) × 5/9
Direction locked to °F → K
Formula & steps
K = (°F + 459.67) × 5/9
K = (°F + 459.67) × 5/9 K = (77 + 459.67) × 5/9 K = 536.67 × 5/9 K = 298.15
Common values
Engineering examples
These values are common engineering examples (datasheet corners, room temperature, and high-temperature ratings). They are not a universal operating-temperature rating for every electronic component.
Natural-language input accepted: 25C, -40 F, 300K.
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Quick Answer
K = (°F + 459.67) × 5/9. 32°F = 273.15 K, 77°F = 298.15 K, −459.67°F = 0 K.
Fahrenheit to Kelvin Converter
K = (°F + 459.67) × 5/9
This is the same as converting °F → °C and then adding 273.15.
Formula and steps
- Add 459.67 to the Fahrenheit reading (shift to Rankine).
- Multiply by 5/9 to change the degree size to kelvin.
- Values below −459.67°F are below absolute zero and are rejected.
Example: 77°F → (77 + 459.67) × 5/9 = 298.15 K.
Fahrenheit to Kelvin chart
| °F | K |
|---|---|
| −459.67 | 0 |
| −40 | 233.15 |
| 32 | 273.15 |
| 68 | 293.15 |
| 77 | 298.15 |
| 98.6 | 310.15 |
| 212 | 373.15 |
Rankine (°R = °F + 459.67) is the Fahrenheit-based absolute scale. This page outputs kelvin, the SI unit.
Related
Design Notes
Electronics datasheets use Celsius exclusively. Standard operating ranges: commercial (0-70°C), industrial (-40 to 85°C), automotive (-40 to 125°C). Junction temperature is the most critical thermal parameter for IC reliability. Common corner values such as -55°C or 125°C are examples, not a universal rating for every part.
Common Mistakes
- 1
Forgetting the offset in Celsius-Fahrenheit conversion — it is NOT a simple multiplication.
- 2
Using ° symbol with Kelvin — correct notation is simply K, not °K.
- 3
Confusing temperature difference with absolute temperature — a 10°C rise = 18°F rise, but 10°C = 50°F.
Engineering Handbox
K = (°F + 459.67) × 5/9 K = (32 + 459.67) × 5/9 K = 491.67 × 5/9 = 273.15
Knowledge Base
How do I convert Fahrenheit to Kelvin?
K = (°F + 459.67) × 5/9. Adding 459.67 shifts to absolute zero on the Fahrenheit scale before converting the degree size.
What is 70°F in Kelvin?
70°F = 294.26 K. (70 + 459.67) × 5/9 = 529.67 × 5/9.