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Calcimator

Stefan–Boltzmann

P = εσAT⁴.

Inputs

Results

Power (W)

914.33

How to Use This Calculator
  1. Enter the blackbody surface temperature T (K).
  2. Set the emitting surface area (m2).
  3. Enter emissivity (1.0 for perfect blackbody, 0.95 for most non-metallic surfaces, 0.05 for polished aluminum).
  4. Review total radiated power in watts.
  5. Use for thermal engineering, building energy analysis, or stellar luminosity estimates.

How the result changes with T (K)

T (K)Power (W)
10,000,000990,047,373,557,400,000,000
35,000,000148,568,983,994,457,340,000,000
65,000,0001,767,296,439,760,806,200,000,000
90,000,0006,495,700,817,910,101,000,000,000

What each input means

T (K)
Absolute temperature in Kelvin. Human body is about 310 K; Sun surface is about 5778 K.
Area (m²)
Surface area of the radiating body in square meters. Average human body surface area is about 1.7-1.9 m2.
ε
Emissivity of the surface (0-1). Human skin is about 0.97; polished metal can be below 0.1.

How this is calculated

Formula

P = ε × σ × A × T⁴

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