watt per square meter to it btu per hour square foot
Convert watt per square meter (W/m²) to it btu per hour square foot (BTU IT/(h·ft²)). Use an editable heat flux converter, conversion formula, and reference table.
1 W/m² = 0.3169983306 BTU IT/(h·ft²)
Conversion formula
One watt per square meter equals 0.3169983306 it btu per hour square foot. Multiply your value in watt per square meter by this factor to get it btu per hour square foot. For the reverse conversion, divide by the same factor.
Worked example
To convert 5 watt per square meter:5 × 0.3169983306 = 1.584991653 BTU IT/(h·ft²)
Conversion table
| watt per square meter (W/m²) | it btu per hour square foot (BTU IT/(h·ft²)) |
|---|---|
| 0.01 | 0.003169983306 |
| 0.1 | 0.03169983306 |
| 1 | 0.3169983306 |
| 2 | 0.6339966613 |
| 5 | 1.584991653 |
| 10 | 3.169983306 |
| 25 | 7.924958266 |
| 50 | 15.84991653 |
| 100 | 31.69983306 |
| 1000 | 316.9983306 |
About these measurements
Heat flux is thermal power per unit surface area.
The base reference used here is the watt per square meter. One watt per square meter is 1 base units; one it btu per hour square foot is 3.154590745 base units.
Important distinctions
Compound units must match the quantity and dimension. Temperature intervals use size factors rather than temperature offsets. Calorie and BTU entries use the explicit definitions shown.
Precision
The converter uses stored conversion factors and floating-point arithmetic. Results display up to ten significant digits, switching to scientific notation for very small or large values. Keep the precision of your original measurement when reporting results.
Common questions
How do I convert W/m² to BTU IT/(h·ft²)?
Multiply the quantity in W/m² by 0.3169983306. You can also type the value into the converter above.
Can I reverse the conversion?
Yes. Use the swap button or open the it btu per hour square foot to watt per square meter converter.
Reference
NIST Guide to the SI — conversion factors and prefix conventions. SI prefixes scale units by powers of ten; the dimension-specific notes above describe the assumptions used on this page.
