Gacha probability calculator
Enter the drop rate (%) and number of pulls to see your chance, and how many pulls give a 50% or 90% chance.
Fill in the form — the result appears here instantly
How it works: Gacha odds
Every pull is independent, so the chance of at least one hit in N pulls is 1 − (1 − rate)^N. At a 1% rate, 100 pulls give about 63% — not 100% — and you need around 230 pulls for 90%.
Set the number of copies above 1 to use the binomial distribution. Games with a pity system give better odds than shown here.
FAQ
Is 100 pulls at 1% a sure thing?
No — about 63.4%.
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