Degrees Fahrenheit to kelvins
Type a value in degrees Fahrenheit to see it in kelvins straight away, or type in the second box to convert back.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the degrees Fahrenheit box.
- Read the result in kelvins as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
K = °F × 0.5555555556 + 255.3722222
Multiply by 0.5555555556, then add 255.3722222, because the two scales have different zero points.
Example
To convert 25 °F to kelvins: 25 × 0.5555555556 + 255.3722222 = 269.261 K.
Conversion table
| Degrees Fahrenheit (°F) | Kelvins (K) |
|---|---|
| -40 | 233.15 |
| -20 | 244.261 |
| -10 | 249.817 |
| 0 | 255.372 |
| 10 | 260.928 |
| 20 | 266.483 |
| 25 | 269.261 |
| 30 | 272.039 |
| 37 | 275.928 |
| 40 | 277.594 |
| 50 | 283.15 |
| 100 | 310.928 |
About the units
- Degree Fahrenheit
- The scale used in the United States, defined exactly by °F = °C × 9/5 + 32. Water freezes at 32 °F and boils at about 212 °F.
- Kelvin
- The SI base unit of thermodynamic temperature, starting at absolute zero (0 K). Since 2019 it is defined by fixing the Boltzmann constant at 1.380649 × 10^-23 J/K.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
What is 0 degrees Fahrenheit in kelvins?
0 °F = 255.372 K. The formula is K = °F × 0.5555555556 + 255.3722222.
How do I convert degrees Fahrenheit to kelvins?
Use K = °F × 0.5555555556 + 255.3722222. For example, 25 °F = 269.261 K.
How many degrees Fahrenheit are in one kelvin?
1 K = -457.87 °F.
Why is temperature conversion not a simple multiplication?
Celsius and Fahrenheit do not start at absolute zero, so converting needs an offset as well as a factor. For example °F = °C × 9/5 + 32, which is why 0 °C is 32 °F, not 0.
At what temperature are Celsius and Fahrenheit equal?
At minus 40: -40 °C is exactly -40 °F.