Generic gacha math · user-supplied inputs

Gacha Banner Rate Comparison Calculator

Compare complete session odds rather than looking only at the advertised per-pull percentages.

Quick answer

Example: A lower per-pull rate can still produce the higher session probability if its pull budget is sufficiently larger. The tool reports both session chances and their absolute gap.

Banner A at-least-one chance —

Banner B at-least-one chance —

Absolute probability difference —

Higher modeled chance —

What this calculator does

Per-pull rate alone does not decide which session has the larger chance because the pull budgets may differ. This comparator converts each rate-and-budget pair into an at-least-one probability before calculating the difference.

The “higher” label describes only the two mathematical scenarios entered. It does not recommend a banner, value a reward, or account for guarantees, changing rates, currencies, or opportunity costs.

Use matching target definitions on both sides. Comparing an exact featured target on one side with any top-rarity result on the other would answer an inconsistent question even if both percentages are valid individually.

Formula

chance for each banner = 1 − (1 − entered target rate) ^ entered pulls

Example: A lower per-pull rate can still produce the higher session probability if its pull budget is sufficiently larger. The tool reports both session chances and their absolute gap.

FAQ

Does the higher chance mean the banner is better?

No. It is only the higher at-least-one probability under the rates and pull counts entered.

Can the two pull budgets be different?

Yes. That is a primary use of the comparison.

What happens if both scenarios match?

The probability difference is zero and the higher-chance result is shown as a tie.

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