Combined Stellar Magnitude Calculator
Combine apparent magnitudes by adding linear fluxes and compare with an entered reference magnitude.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Use a bright-object reference internally to add flux without adding logarithmic magnitude numbers directly.
Relative flux=10^(−0.4(m−reference)); combined m=min m−2.5log10Σ10^(−0.4(m−min m))
Worked example
Two equal magnitude1 objects combine to magnitude1−2.5log10(2), approximately0.247425.
Assumptions and input details
All inputs must use the same passband/zero-point system; magnitudes limited to±100. No Vega/AB zero-point conversion, extinction, distance or instrument response inference.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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