How to use the stellar luminosity calculator
Estimate a star's luminosity from radius and temperature. Enter radius, temperature in the fields above; the luminosity, luminosity are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- R — Radius (solar radii)
- T — Temperature (K)
Worked example
With radius = 1 solar radii, temperature = 5772 K, the calculator gives luminosity ≈ 3.828 × 10²⁶ W; luminosity ≈ 0.9999976 solar.
Frequently asked questions
What is the formula for the stellar luminosity calculation?
Luminosity (W) = 4 × π × (R × 6.957e8)^2 × SIGMA × T^4. Luminosity (solar) = [Luminosity] / 3.828e26. Here R is radius (solar radii), T is temperature (K).
What inputs do I need for the stellar luminosity calculator?
You need radius in solar radii, temperature in K. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.