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Both calculators run independently — change the inputs on either side to compare results.

Astronomy

Stellar Luminosity Calculator

Compute a star's luminosity in solar units (L☉) from its radius and surface temperature via the Stefan-Boltzmann law. The fundamental relationship between stellar size, temperature, and total energy output — and the basis of the Hertzsprung-Russell diagram.

Astronomy

Schwarzschild Radius Calculator

Compute the Schwarzschild radius — the event horizon size of a non-rotating black hole — from its mass via r_s = 2GM/c². The defining length scale of black holes, equal to about 3 km per solar mass.

Key differences

Stellar Luminosity CalculatorSchwarzschild Radius Calculator
CategoryAstronomyAstronomy
Inputs required21
ResultStellar Luminosity (L☉)Schwarzschild Radius (km)
What it doesCompute a star's luminosity in solar units (L☉) from its radius and surface temperature via the Stefan-Boltzmann law. The fundamental relationship between stellar size, temperature, and total energy output — and the basis of the Hertzsprung-Russell diagram.Compute the Schwarzschild radius — the event horizon size of a non-rotating black hole — from its mass via r_s = 2GM/c². The defining length scale of black holes, equal to about 3 km per solar mass.