Convert Watt per square metre to Watt per square millimetre
Convert Watt per square metre (W/m²) to Watt per square millimetre (W/mm²) instantly and accurately.
Conversion Formula
W/mm² = W/m² × 1.000000000e-6
About Watt per square metre
The watt per square metre (W/m²) is the SI coherent unit for heat flux density and irradiance. Solar irradiance at Earth's surface ≈ 1000 W/m²; solar constant ≈ 1361 W/m²; human skin radiative emission ≈ 100 W/m²; global average geothermal flux ≈ 0.087 W/m². Referenced in ISO 80000-4. 1 W/m² = 1 J/(s·m²) = 10⁻³ kW/m².
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.
Quick Reference Table
| Watt per square metre (W/m²) | Watt per square millimetre (W/mm²) |
|---|---|
| 1 W/m² | 1 × 10-6 W/mm² |
| 2 W/m² | 2 × 10-6 W/mm² |
| 5 W/m² | 5 × 10-6 W/mm² |
| 10 W/m² | 1 × 10-5 W/mm² |
| 25 W/m² | 2.5 × 10-5 W/mm² |
| 50 W/m² | 5 × 10-5 W/mm² |
| 100 W/m² | 1 × 10-4 W/mm² |