Convert Watt per square millimetre to Watt per square inch
Convert Watt per square millimetre (W/mm²) to Watt per square inch (W/in²) instantly and accurately.
Conversion Formula
W/in² = W/mm² × 645.16
About Watt per square millimetre
The watt per square millimetre (W/mm²) equals exactly 10⁶ W/m². Used in high-power laser material processing - cutting, welding, and additive manufacturing - and electron beam applications. A 1 kW laser focused to 1 mm² achieves 1 W/mm². Numerically equal to MW/m². 1 W/mm² = 10⁶ W/m² = 100 W/cm².
About Watt per square inch
The watt per square inch (W/in²) equals 1/(6.4516×10⁻⁴) ≈ 1550.003 W/m² (1 in = 0.0254 m). Used in US electronics thermal management for PCB power density, semiconductor die heat flux, and power module ratings. 1 W/in² ≈ 1550 W/m² ≈ 0.155 W/cm².
Quick Reference Table
| Watt per square millimetre (W/mm²) | Watt per square inch (W/in²) |
|---|---|
| 1 W/mm² | 645.16 W/in² |
| 2 W/mm² | 1290.32 W/in² |
| 5 W/mm² | 3225.8 W/in² |
| 10 W/mm² | 6451.6 W/in² |
| 25 W/mm² | 16129 W/in² |
| 50 W/mm² | 32258 W/in² |
| 100 W/mm² | 64516 W/in² |