Heat Flux Converter
Convert heat-transfer rate per area between W/m², W/cm² and Btu or calorie area-time units.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Express the same heat rate per area in W/m², combining the selected energy, area and time definitions.
q_SI=value×joules per energy unit/(seconds per time unit×square meters per area unit)
Worked example
1 W/cm² is 10000 W/m². One Btu(IT)/(h·ft²) is approximately 3.15459075 W/m².
Assumptions and input details
A signed value can describe a chosen heat-flow direction. These units describe energy per area per time, at the same conditions. Total watts require a specified area; cumulative energy per area additionally requires time. No surface temperature, emissivity, heat-transfer coefficient or solar yield is inferred.
References: NIST: unit conversion factors
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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