watt per square meter
Intensityexact by definition
The watt per square metre is the SI unit of intensity, or irradiance, the power crossing unit area perpendicular to the flow. As a coherent derived unit its relation to the SI base units is exact by definition. For scale, the solar constant above the atmosphere is about 1361 W/m² and full midday sun at the ground is conventionally taken as 1000 W/m².
Watch out: Radiant intensity in watts per square metre is a physical power flux, not the same thing as illuminance in lux, which weights the spectrum by human eye sensitivity. There is no fixed conversion between the two without knowing the source spectrum.
| 1 | 1 |
One watt per square meter in every intensity unit
| 1,000,000 | microwatt per square meter (μW/m²) | |
| 1,000 | milliwatt per square meter (mW/m²) | |
| 100 | microwatt per square centimeter (μW/cm²) | |
| 1 | watt per square meter (W/m²)this unit | |
| 0.316998 | BTU per hour square foot (BTU/(h·ft²)) | |
| 0.1 | milliwatt per square centimeter (mW/cm²) | |
| 0.00143403 | langley per minute (Ly/min) | |
| 0.001 | kilowatt per square meter (kW/m²) | |
| 0.0001 | watt per square centimeter (W/cm²) | |
| 1.00000e-10 | megawatt per square centimeter (MW/cm²) |
Solvers that use intensity