Unit converter

Heat Flux Density converter

Convert heat flux density units including watts per square meter and BTU per square foot-hour.

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1 W/m² = 0.001 kW/m²

All Heat Flux Density units

From 1 W/m²
UnitValue
Watt/square meter W/m² 1
Kilowatt/square meter kW/m² 0.001
Watt/square centimeter W/cm² 0.0001
Watt/square inch W/in² 0.00064516
Joule/square meter/second J/(m²·s) 1
Btu (IT)/square foot/second Btu/(ft²·s) 0.0000880551
Btu (IT)/square foot/minute Btu/(ft²·min) 0.0052833055
Btu (IT)/square foot/hour Btu/(ft²·h) 0.3169983306
Calorie (IT)/square centimeter/second cal/(cm²·s) 0.0000238846
Kilocalorie (IT)/square meter/hour kcal/(m²·h) 0.8598452279
Kilocalorie (IT)/square meter/second kcal/(m²·s) 0.0002388459
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Common tasks

Reference

How heat flux density conversion works

Heat flux density measures the rate of heat transfer through a unit area. Values are normalized to Watt/square meter before conversion to the requested output unit.

Values are converted to watt/square meter first, then from that reference into the requested unit. Keeping a single documented reference reduces inconsistent pair-by-pair constants.

Accuracy note: SI relationships follow the cited reference. Conventional and domain-specific factors use the established ConvertWin factor inventory; verify safety-critical work against the governing standard.

Unit reference

UnitSymbol1 unit in W/m²
Watt/square meterW/m²1
Kilowatt/square meterkW/m²1,000
Watt/square centimeterW/cm²10,000
Watt/square inchW/in²1,550.003101
Joule/square meter/secondJ/(m²·s)1
Btu (IT)/square foot/secondBtu/(ft²·s)11,356.526680000001
Btu (IT)/square foot/minuteBtu/(ft²·min)189.2754447
Btu (IT)/square foot/hourBtu/(ft²·h)3.154590745
Calorie (IT)/square centimeter/secondcal/(cm²·s)41,868
Kilocalorie (IT)/square meter/hourkcal/(m²·h)1.163
Kilocalorie (IT)/square meter/secondkcal/(m²·s)4,186.8

Long-tail directory

Every indexed conversion

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Primary source

Definitions and standards

The SI framework is checked against NIST Guide for the Use of the International System of Units. Conventional factors are retained from the extended ConvertWin inventory and carry the accuracy note shown above.

See Methods & sources for rounding rules, exact-value handling, and review policy.

Questions

Heat Flux Density FAQ

What is the reference unit for heat flux density conversions?

ConvertWin uses watt/square meter (W/m²) as the internal reference for this category, then converts to the selected output unit.

How accurate is this heat flux density converter?

SI relationships follow the cited reference. Conventional and domain-specific factors use the established ConvertWin factor inventory; verify safety-critical work against the governing standard.