// conversions › 3 · Thermal, Materials & Everyday
Convert heat flux density between W/m² and BTU/(hr·ft²) via the SI base.
result = value × (from→W/m²) ÷ (to→W/m²)
It converts convert heat flux density between w/m² and btu/(hr·ft²) via the si base by first normalising your value to the SI base unit (watt per square metre) and then scaling to your chosen target unit. This hub-and-spoke approach guarantees every unit pair is internally consistent.
1000 W/m² to BTU/(hr·ft²): 1000 ÷ 3.1546 ≈ 317.0.
Skin comfort loses about 50 W/m²; bright sunlight delivers about 1000 W/m² (the basis of solar panel ratings); a spacecraft heat shield in re-entry can exceed 1,000,000 W/m².
Solar engineering, re-entry thermal protection and heat-exchanger design.
Conversions are exact ratios where the units are defined exactly (most SI and imperial units) and best-available constants otherwise. Extremely large or small magnitudes are shown in general (g) format; round-tripping through the base unit may introduce tiny floating-point differences in the final decimal places.