Radiation Heat Transfer Calculator
Calculate radiative heat transfer Q = εσA(T₁⁴ - T₂⁴) with common emissivity reference values
Radiation Heat Transfer Calculator
Calculate radiative heat exchange between a surface and surroundings.
Formula
Q = ε · σ · A · (T₁⁴ − T₂⁴)
σ = 5.67 × 10⁻⁸ W/(m²·K⁴) — temperatures must be in Kelvin
0 (perfect reflector) – 1 (black body)
Emissivity Presets
Results
Heat Transfer Rate Q
17857.08 W
Surface emits heat to surroundings
Heat Flux q
17857.08 W/m²
Linearised h_rad
37.2022 W/m²K
Calculation Steps
How to Use This Calculator
Enter your input values
Fill in all required input fields for the Radiation Heat Transfer Calculator. Most fields include unit selectors so you can work in your preferred unit system.
Review your inputs
Double-check that all values are correct and that you have selected the right units for each field. Incorrect units are the most common source of calculation errors.
Read the results
The Radiation Heat Transfer Calculator instantly computes the output and displays results with units. All calculations happen in your browser — no loading time and no data sent to a server.
Formula Reference
Stefan-Boltzmann Law
Q = ε·σ·A·(T₁⁴ − T₂⁴)
Variables: ε = emissivity, σ = Stefan-Boltzmann constant (5.67×10⁻⁸ W/m²·K⁴), T in Kelvin
When to Use This Calculator
- •Use the Radiation Heat Transfer Calculator when solving homework or exam problems that require quick numerical verification of your hand calculations.
- •Use it during the design phase to rapidly iterate on parameters before running detailed finite element simulations.
- •Use it when reviewing a colleague's calculation or checking a vendor's data sheet for plausibility.
- •Use it to generate reference data for a technical report or presentation without manual computation.
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