Star Magnitude Brightness Comparator
Enter two apparent magnitudes or a magnitude difference to calculate the relative brightness ratio locally.
A QUICK WALKTHROUGH
How to use this tool
- Enter the brighter and fainter apparent magnitudes.
- Review the magnitude difference and 10^(0.4 × Δm) ratio.
- Interpret the result only as a comparison of the supplied values.
Formula
For a magnitude difference Δm = m_fainter − m_brighter, the ratio is 10^(0.4 × Δm). Larger positive Δm means the first object is brighter by the displayed ratio.
Scope
This compares the numeric apparent magnitudes you provide. It does not infer absolute luminosity, distance, physical properties, or observing conditions.
GOOD TO KNOW
Common questions
Does a larger magnitude mean brighter?
No. On the apparent magnitude scale, a smaller numeric magnitude is brighter.
Does this calculate distance?
No. It only applies the brightness-ratio formula to the entered values.