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Gacha Probability Calculator

Enter the rate per pull and how many times you will pull to see your odds instantly.

Your text and files never leave your browser — nothing is sent to a server.

Pity is treated as a guaranteed hit on that pull count since your last hit, with the counter resetting after any hit.

At least 1 in {n} pulls
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Chance of no hits
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Expected hits
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Average pulls per hit
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Pulls needed for a target chance

Chance of at least 1Pulls needed

These are math estimates that assume every pull is independent. Real games may work differently, so check the rates the game publishes.

How to use

  1. The chance of at least one hit is 1 − (1 − p)ⁿ and the average number of pulls per hit is 1 ÷ p, where p is the rate per pull and n is the number of pulls.
  2. Enter the rate shown in the game and the number of pulls you plan. Set “Target hits” to 2 or more to also see the chance of getting that many.
  3. If the game has pity, enter the pull count where a hit is guaranteed. The counter is assumed to restart whenever you get a hit.
  4. The table shows how many pulls give a 50%, 90%, 95% or 99% chance. Add a cost per pull to see what that would cost.

FAQ

With a 1% rate, am I guaranteed a hit in 100 pulls?

No. The chance of at least one hit in 100 pulls is about 63.4%. You need about 459 pulls for a 99% chance.

I have missed many times. Is my next pull more likely to hit?

Not without pity. Each pull is independent with the same rate, so earlier misses do not change the next one. Believing otherwise is the gambler’s fallacy. Only a pity system brings a guaranteed hit closer.

How is pity handled?

The pull at the pity count since your last hit always wins, and the counter goes back to zero after any hit. Soft pity (rates that rise gradually) and 50/50 featured rules are not modelled.

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