The stellar magnitude scale is backward and logarithmic: smaller numbers mean brighter stars, and every step of one magnitude is a fixed brightness ratio of about two point five one two, the fifth root of one hundred. That means a five magnitude gap is exactly one hundred times in brightness. This calculator turns any magnitude difference between two stars into a plain brightness ratio, so you can say how many times brighter one object is than another. Enter two magnitudes or a single difference and it reports the factor both ways. It is handy for comparing planets, variable stars or the faintest object your eye or scope can reach. Everything is computed locally in your browser.
The stellar magnitude scale is backward and logarithmic: smaller numbers mean brighter stars, and every step of one magnitude is a fixed brightness ratio of about two point five one two, the fifth root of one hundred. That means a five magnitude gap is exactly one hundred times in brightness.
Yes. Star Brightness Ratio Calculator is completely free, with no sign-up and no usage limits.
Yes. Star Brightness Ratio Calculator runs in any modern web browser. There is nothing to download or install.
Yes. Star Brightness Ratio Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.