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Both calculators run independently — change the inputs on either side to compare results.
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.
Fill in the required fields to see your result.
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.
Fill in the required fields to see your result.
Key differences
| Schwarzschild Radius Calculator | Stellar Luminosity Calculator | |
|---|---|---|
| Category | Astronomy | Astronomy |
| Inputs required | 1 | 2 |
| Result | Schwarzschild Radius (km) | Stellar Luminosity (L☉) |
| What it does | 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. | 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. |