Convert Per Degree Fahrenheit to Per Kelvin (°F⁻¹ to K⁻¹)
1 per degree Fahrenheit (°F⁻¹) = 1.8 per kelvin (K⁻¹). 1 K⁻¹ = 0.5555555556 °F⁻¹. Example: 0.0000065 °F⁻¹ = 0.0000065 × 1.8 = 0.0000117 K⁻¹.
Also searched as per degree Fahrenheit to K⁻¹, per degree Fahrenheit in K⁻¹, per degree Fahrenheit into per kelvin, °F⁻¹ to K⁻¹, °F⁻¹ in per kelvin, °F⁻¹ into per kelvin, per degree Fahrenheit to per kelvin, °F⁻¹ to per kelvin converter and how many per kelvin in a per degree Fahrenheit.
1 °F⁻¹ = 1.8 K⁻¹
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk per degree Fahrenheit to per kelvin converter to paste a column from Excel.
How to Convert Per Degree Fahrenheit to Per Kelvin
- 1 °F⁻¹ = 1.8 K⁻¹
- 1 K⁻¹ = 0.5555555556 °F⁻¹
- Example: convert 0.0000065 °F⁻¹ to K⁻¹: 0.0000065 °F⁻¹ = 0.0000065 × 1.8 K⁻¹ = 0.0000117 K⁻¹
Formula
K⁻¹ = °F⁻¹ × 1.8
Derivation from SI units:
- A Fahrenheit degree is 5/9 of a kelvin, so 1/°F = 1.8/K (exact)
- The SI unit of the coefficient of thermal expansion: relative change in length (m/m) per kelvin
Both units are defined exactly, so the factor is exact. Per Degree Fahrenheit definition: per degree Fahrenheit; Per Kelvin definition: per kelvin.
Worked examples
- Steel at 0.0000065 °F⁻¹ is 0.0000117 K⁻¹.
0.0000065 °F⁻¹ × 1.8 = 0.0000117 K⁻¹ - Aluminium at about 0.0000128 °F⁻¹ is 0.00002304 K⁻¹.
0.0000128 °F⁻¹ × 1.8 = 0.00002304 K⁻¹
Per Degree Fahrenheit to Per Kelvin conversion table
| Per Degree Fahrenheit (°F⁻¹) | Per Kelvin (K⁻¹) |
|---|---|
| 0.0000003 °F⁻¹ | 5.4 × 10⁻⁷ K⁻¹ |
| 0.0000005 °F⁻¹ | 9 × 10⁻⁷ K⁻¹ |
| 0.000005 °F⁻¹ | 0.000009 K⁻¹ |
| 0.0000065 °F⁻¹ | 0.0000117 K⁻¹ |
| 0.0000096 °F⁻¹ | 0.00001728 K⁻¹ |
| 0.0000128 °F⁻¹ | 0.00002304 K⁻¹ |
| 0.00003 °F⁻¹ | 0.000054 K⁻¹ |
| 0.00005 °F⁻¹ | 0.00009 K⁻¹ |
| 0.0001 °F⁻¹ | 0.00018 K⁻¹ |
| 0.0005 °F⁻¹ | 0.0009 K⁻¹ |
Where it's used
Coefficients of thermal expansion in 1/°F from US codes and handbooks are converted to 1/K (or 1/°C) for SI calculations. Multiply by 1.8.
Per Degree Fahrenheit to other thermal expansion coefficient units
| Conversion | 1 °F⁻¹ equals |
|---|---|
| per degree Fahrenheit to per kelvin | 1.8 K⁻¹ |
| per degree Fahrenheit to ppm per kelvin | 1800000 ppm/K |
| per degree Fahrenheit to per degree Celsius | 1.8 °C⁻¹ |
| per degree Fahrenheit to ppm per degree Fahrenheit | 1000000 ppm/°F |
Frequently asked questions
Is 1/°C the same as 1/K?
Yes. Celsius and kelvin degrees are the same size, so an expansion coefficient has the same value in 1/°C and 1/K.
How many per kelvin are in 1 per degree Fahrenheit?
1 °F⁻¹ = 1.8 K⁻¹.
How do I convert per degree Fahrenheit to per kelvin?
Multiply the value in °F⁻¹ by 1.8. For example, 0.0000065 °F⁻¹ × 1.8 = 0.0000117 K⁻¹.
Is the °F⁻¹ to K⁻¹ conversion exact?
Yes. Both units are defined exactly, and 1 °F⁻¹ is exactly 1.8 K⁻¹.
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "degree Fahrenheit".
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 4, degree Celsius.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Per Degree Fahrenheit to Per Kelvin (°F⁻¹ to K⁻¹). Retrieved October 25, 2026, from https://scientificconverters.com/thermal-expansion/per-degree-fahrenheit-to-per-kelvin/
IEEE
Scientific Converters, "Convert Per Degree Fahrenheit to Per Kelvin (°F⁻¹ to K⁻¹)," scientificconverters.com. Accessed: Oct. 25, 2026. [Online]. Available: https://scientificconverters.com/thermal-expansion/per-degree-fahrenheit-to-per-kelvin/