Star brightness converter
Convert a star’s magnitude into how many times brighter or fainter it actually is. The scale runs backwards, and five steps is a factor of a hundred.
That's 41× as bright as Polaris, while the naked-eye limit is 1.58× fainter. That is bright enough to see with the naked eye from a dark site.
What it means
How bright is that?
These are apparent magnitudes: how bright something looks from Earth, not how much light it truly gives out.
Every unit
Your brightness in every unit
Learn
Three things worth knowing
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Five magnitudes is a hundred times
So one magnitude is the fifth root of a hundred, about 2.512. Sirius at −1.46 is about 24 times brighter than Polaris at 1.98.
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Hipparchus ranked the stars
Around 130 BC he called the brightest stars "first magnitude" and the faintest "sixth". Pogson fixed the hundredfold ratio in 1856 to match that old ranking.
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Bigger means fainter
A magnitude 10 star is far fainter than a magnitude 1 star. The scale counts down towards brightness, and keeps going into negative numbers.
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Background
About magnitude
Magnitude is a logarithmic brightness scale that runs backwards: the brightest objects have the most negative numbers. Five magnitudes is exactly a hundredfold difference in brightness, so one magnitude is about 2.512 times.
The naked eye reaches magnitude 6 under a dark sky, and barely magnitude 3 in a city.