Heat Flux Density

Convert w/m² to btu/hr·ft²

1 watt per square meter equals 0.31699833 btu (it) per hour ft². Enter a value below to convert instantly.

1 W/m²
0.31699833 BTU/(h·ft²)

Multiply the number of watts per square meter by 0.316998330628 to get btu (it) per hour ft². How this is calculated

Need the other direction? Convert btu (it) per hour ft² to watt per square meter →

Formula

Multiply the number of watts per square meter by 0.316998330628 to get btu (it) per hour ft².

Step by step

  1. Start with 1 W/m².
  2. Multiply by the conversion factor 0.316998330628.
  3. 1 × 0.316998330628 = 0.31699833 BTU/(h·ft²).

Watts per Square Meter to BTU (IT) per Hour ft² conversion table

Conversion table from Watts per Square Meter to BTU (IT) per Hour ft²
Watts per Square Meter (W/m²) BTU (IT) per Hour ft² (BTU/(h·ft²))
1 0.31699833
5 1.5849917
10 3.1699833
50 15.849917
100 31.699833
500 158.49917
1,000 316.99833

Convert Watt per Square Meter to other heat flux density units

1 W/m² expressed in every other heat flux density unit on this site.

  • Kilowatt per Square Meter kW/m² 0.001
  • Milliwatt per Square Meter mW/m² 1,000
  • Watt per Square Centimeter W/cm² 0.0001
  • Watt per Square Inch W/in² 0.00064516
  • Watt per Square Foot W/ft² 0.09290304
  • Kilocalorie (IT) per Hour m² kcal/(h·m²) 0.85984523
  • Kilocalorie (IT) per Hour ft² kcal/(h·ft²) 0.079882236
  • Calorie (IT) per Second cm² cal/(s·cm²) 0.00002388459
  • BTU (IT) per Hour ft² BTU/(h·ft²) 0.31699833
  • BTU (IT) per Minute ft² BTU/(min·ft²) 0.0052833055
  • BTU (IT) per Second ft² BTU/(s·ft²) 0.000088055092
  • BTU (IT) per Second in² BTU/(s·in²) 6.1149369e-7
  • Erg per Second cm² erg/(s·cm²) 1,000
  • Horsepower per Square Foot hp/ft² 0.00012458503
  • Horsepower (metric) per Square Foot PS/ft² 0.00012631298
  • Calorie (IT) per Minute cm² cal/(min·cm²) 0.0014330754
  • Calorie (IT) per Hour cm² cal/(h·cm²) 0.085984523
  • Calorie (th) per Second cm² cal(th)/(s·cm²) 0.000023900574
  • Calorie (th) per Minute cm² cal(th)/(min·cm²) 0.0014340344
  • Calorie (th) per Hour cm² cal(th)/(h·cm²) 0.086042065
  • Dyne per Hour Centimeter dyn/(h·cm) 3,600,000
  • Erg per Hour mm² erg/(h·mm²) 36,000
  • Foot-pound per Minute ft² ft·lbf/(min·ft²) 4.111306
  • BTU (th) per Second in² BTU(th)/(s·in²) 6.1190291e-7
  • BTU (th) per Second ft² BTU(th)/(s·ft²) 0.00008811402
  • BTU (th) per Minute ft² BTU(th)/(min·ft²) 0.0052868412
  • BTU (th) per Hour ft² BTU(th)/(h·ft²) 0.31721047
  • CHU per Hour ft² CHU/(h·ft²) 0.17611018

About the watt per square meter

The watt per square meter (W/m²) is a SI unit of heat flux density.

About the btu (it) per hour ft²

The btu (it) per hour ft² (BTU/(h·ft²)) is a Imperial unit of heat flux density.

Where this conversion is used

Converting watts per square meter to btu (it) per hour ft² comes up when solar irradiance, building envelopes, and electronics cooling. Full midday sunlight is close to 1,000 W/m², a useful reference point when sizing panels or estimating solar gain.

Related conversions

Frequently asked questions

How many btu (it) per hour ft² are in a watt per square meter?

One watt per square meter equals 0.31699833 btu (it) per hour ft².

How do you convert watts per square meter to btu (it) per hour ft²?

Multiply the number of watts per square meter by 0.316998330628 to get btu (it) per hour ft².

What is 1 btu (it) per hour ft² in watts per square meter?

One btu (it) per hour ft² equals 3.1545907 watts per square meter.

When would I convert watts per square meter to btu (it) per hour ft²?

This conversion is common when solar irradiance, building envelopes, and electronics cooling.

Conversion factors are based on internationally agreed unit definitions. See our methodology and sources for details on how these values are verified.