Convert Degree Fahrenheit per watt to Millikelvin per watt

Convert Degree Fahrenheit per watt (°F/W) to Millikelvin per watt (mK/W) instantly and accurately.

Degree Fahrenheit per watt (°F/W)
Millikelvin per watt (mK/W)

Conversion Formula

mK/W = °F/W × 555.5555556

About Degree Fahrenheit per watt

The degree Fahrenheit per watt (°F/W) equals exactly 5/9 K/W ≈ 0.5556 K/W. It appears in US power electronics datasheets and legacy JEDEC thermal specifications where junction-to-case resistance is reported in °F/W rather than °C/W or K/W. A device rated 5 °F/W has R = 5 × 5/9 ≈ 2.78 K/W. 1 °F/W = 5/9 K/W.

About Millikelvin per watt

The millikelvin per watt (mK/W) equals exactly 10⁻³ K/W. It is used for ultra-low thermal resistances in high-conductivity materials such as diamond heat spreaders (≈ 0.3 mK/W per mm thickness for 1 cm² area), liquid metal TIMs, and cryogenic heat links. Measuring at this scale requires precision power dissipation and calorimetric temperature sensing. 1 mK/W = 10⁻³ K/W.

Quick Reference Table

Degree Fahrenheit per watt (°F/W)Millikelvin per watt (mK/W)
1 °F/W555.556 mK/W
2 °F/W1111.11 mK/W
5 °F/W2777.78 mK/W
10 °F/W5555.56 mK/W
25 °F/W13888.9 mK/W
50 °F/W27777.8 mK/W
100 °F/W55555.6 mK/W

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