Calculate the brightness ratio between two stars from their magnitude difference, or vice versa. The astronomical magnitude scale is logarithmic, where a difference of 5 magnitudes equals a brightness factor of 100.
Enter your values below
Apparent or absolute magnitude of star 1
Apparent or absolute magnitude of star 2
Ratio of fluxes (alternative input)
How this calculator works
Magnitude difference equals negative 2.5 times the base-10 logarithm of the flux ratio.
Common questions about this calculator
These calculators are for educational and informational purposes only. While we strive for accuracy, results should be verified for critical applications. Always consult authoritative sources for engineering or scientific work.
