Convert ppm per degree Fahrenheit to Per kelvin

Convert ppm per degree Fahrenheit (ppm/°F) to Per kelvin (1/K) instantly and accurately.

ppm per degree Fahrenheit (ppm/°F)
Per kelvin (1/K)

Conversion Formula

1/K = ppm/°F × 1.800000000e-6

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.

About Per kelvin

The per kelvin (1/K = K⁻¹) is the SI unit for linear thermal expansion coefficient (α = (1/L) dL/dT). Used in NIST databases, FEA material cards, and thermodynamics textbooks. Liquid mercury: ≈6.1 × 10⁻⁵ /K; aluminium: ≈2.3 × 10⁻⁵ /K; fused silica: ≈5.5 × 10⁻⁷ /K. 1 /K = 10⁶ ppm/K = 1/°C.

Quick Reference Table

ppm per degree Fahrenheit (ppm/°F)Per kelvin (1/K)
1 ppm/°F1.8 × 10-6 1/K
2 ppm/°F3.6 × 10-6 1/K
5 ppm/°F9 × 10-6 1/K
10 ppm/°F1.8 × 10-5 1/K
25 ppm/°F4.5 × 10-5 1/K
50 ppm/°F9 × 10-5 1/K
100 ppm/°F0.00018 1/K

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