ConverterHub

Gacha Pity Calculator

Find your odds of at least one drop

Result

41.82%
166.67

How it is calculated

The tool assumes every pull has the same independent drop chance. With p = rate ÷ 100 and N pulls, the chance of at least one success is P = (1 − (1 − p)N) × 100 as a percentage, and the expected number of pulls for the first success is 1 ÷ p. The rate is entered in percent (0.6 for 0.6%) and must be above 0 and at most 100. Attempts must be at least 1. It does not model a rising rate or a guaranteed pity pull: if the game raises the odds as you approach the pity counter, the real chance is higher than shown.

Worked example

An item drops at 0.6% per pull and you plan 90 pulls. Here p = 0.006, so the chance of missing on one pull is 0.994. Raise 0.994 to the 90th power, about 0.5818, and subtract from 1: the chance of at least one drop is 41.82%. The expected number of pulls is 1 ÷ 0.006 = 166.67. Even at 166 pulls the chance is only 63.18%, so going past the average is common.

Try this example →

Common mistakes

  • Believing that the expected number of pulls (166.67) guarantees a drop. At that point the chance is still only about 63%.
  • Entering the rate as a fraction (0.006) instead of a percent (0.6). The tool would read it as 0.006%.
  • Ignoring soft pity or a guaranteed pull. The tool uses a flat rate, so it underestimates the chance in games that raise odds late.
  • Treating earlier failed pulls as improving the next one. Each pull is independent, unless the game states a pity counter.
  • Using the sum of rates for a pool of several featured items. Calculate the chance for the exact item you want.

About this calculator

The probability of getting at least one success across n independent pulls at a fixed drop rate p is 1 − (1−p)ⁿ — one minus the probability that every single pull fails. This complement trick is the standard way to answer "how many tries until I probably get it" questions for any independent, fixed-probability event, and it's the baseline math behind gacha-game loot odds before any pity system kicks in.

Many gacha games layer a pity counter on top of this base rate — a guaranteed drop after a fixed number of consecutive failures — specifically because the raw geometric odds this calculator computes can leave a small but real chance of very long unlucky streaks. Players use this calculation to gauge realistic expectations before a pull session, while game designers use the same math when tuning base drop rates and pity thresholds to hit a target average cost per item.

Was this helpful?

You can pick up to 3 reactions.

Comments (0)

  • Be the first to comment.

Popular calculators

Loan Calculator

Monthly payment, total interest and full amortization schedule.

Percentage Calculator

Percent change, percent of, and ratio calculations.

Discount Calculator

Calculate final price, savings, and discount amount.

BMI Calculator

Body mass index from height and weight (metric or imperial).

Age Calculator

Compute your exact age in years, months and days from a birth date.

Compound Interest Calculator

Calculate the final amount and interest earned with compounding.

All Calculators