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Win probability
—%
Miss probability
—%
How to Use
Input Mode: Fraction
Enter a numerator and denominator to specify the probability. For example, “1 / 100” equals a 1% chance per draw.
Input Mode: Percent
Enter the probability directly as a percentage. For example, entering “1” means a 1% chance per draw.
Calculation Mode: At Least Once
Calculates the probability of winning at least once across N draws, and the probability of getting no wins at all. Great for calculating gacha or lottery odds.
Calculation Mode: Consecutive
Calculates the probability of winning on every single one of N consecutive draws. Useful when all attempts must succeed.
Calculation Mode: Min. Draws
Calculates the minimum number of draws needed to reach a target win probability (e.g., 80%). Enter a price per draw to also see the estimated total budget.