Convert ppb per kelvin to ppm per degree Fahrenheit
Convert ppb per kelvin (ppb/K) to ppm per degree Fahrenheit (ppm/°F) instantly and accurately.
Conversion Formula
ppm/°F = ppb/K × 0.0005555555556
About ppb per kelvin
The ppb/K (parts per billion per kelvin) equals 10⁻⁹ /K and is the resolution unit for ultra-low-CTE materials. Zerodur Class 0 (±0.02 ppb/K) and ULE titanium-silicate glass (±0.03 ppb/K) at 20 °C are characterised in ppb/K for gravitational-wave interferometers and space telescope optical benches. 1 ppb/K = 10⁻⁹ /K = 10⁻³ ppm/K.
About ppm per degree Fahrenheit
The ppm/°F (= μin/(in·°F) exactly) equals 9/5 × 10⁻⁶ /K ≈1.8 × 10⁻⁶ /K and is the dominant CTE unit in US ASTM standards, ASME piping codes, and mechanical engineering handbooks. Steel ≈6.7 ppm/°F; aluminium ≈12.8 ppm/°F; copper ≈9.4 ppm/°F. 1 ppm/°F = 9/5 × 10⁻⁶ /K.
Quick Reference Table
| ppb per kelvin (ppb/K) | ppm per degree Fahrenheit (ppm/°F) |
|---|---|
| 1 ppb/K | 0.000555556 ppm/°F |
| 2 ppb/K | 0.00111111 ppm/°F |
| 5 ppb/K | 0.00277778 ppm/°F |
| 10 ppb/K | 0.00555556 ppm/°F |
| 25 ppb/K | 0.0138889 ppm/°F |
| 50 ppb/K | 0.0277778 ppm/°F |
| 100 ppb/K | 0.0555556 ppm/°F |