Constants & Units · constant
Stefan–Boltzmann constant
σ = 5.670 374 419… × 10⁻⁸ W m⁻² K⁻⁴
- Unit
- W m⁻² K⁻⁴
- Value
- 5.670 374 419… × 10⁻⁸
- Exact
- yes
- Note
- How brightly a hot body glows. Exact since 2019 because its ingredients are.
- Symbol
- σ
- Category
- Thermodynamic
- Numeric
- 5.670374419e-08
- Uncertainty
- exact (from h, c, k_B)
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