All Probability Calculators
Choose the calculator that matches the way your item is drawn. Fixed-rate pulls, blind boxes, random packs, and shrinking prize pools need slightly different assumptions.
Gacha Probability Calculator
Estimate the chance of getting at least one target item after a set number of gacha pulls. Enter the listed drop rate, your planned pulls, and an optional cost per pull.
Blind Box Probability Calculator
Estimate your chance of pulling a specific figure, secret item, or any design you want from a blind box series.
Ichiban Kuji Odds Calculator
Calculate the chance of drawing at least one target prize from a remaining prize pool where tickets are removed after each draw.
Random Booster Probability Calculator
Estimate the odds of pulling a desired variant from random booster packs, collectible toy packs, or mystery assortments.
At Least One Success Calculator
Use this general probability tool for any repeated chance event: pulls, boxes, prize entries, packs, or attempts with the same success rate.
Expected Cost Calculator
Estimate the expected number of attempts for one success and the cost to reach a chosen probability target.
Which calculator should I use?
Use the gacha or at least one success calculator when each attempt has the same listed rate. Use the blind box or random booster calculators when you know the number of possible variants. Use the Ichiban Kuji-style calculator when prizes or tickets are removed after each draw.
If you are comparing random buying with a direct purchase, the expected cost calculator is usually the best place to start. It shows the long-run average and the cost needed for a chosen confidence level.
Before you calculate
Check the current rate, set size, or remaining prize pool from the seller or game first. Old rates, sold tickets, weighted variants, and guarantee systems can change the real result.
Useful guides
Read the assumptions before you rely on a number for a buying decision.
How Gacha Probability Works
Learn how gacha probability works, why repeated pulls do not add up directly, and how to read at least-one-success odds.
Blind Box Odds Explained
Understand blind box odds, equal variant assumptions, secret item limits, duplicate risk, and how to compare boxes with resale prices.
Prize Draw Odds Without Replacement
Learn why prize draws with removed tickets need without-replacement probability and how remaining pool counts change your odds.
Expected Cost vs Guaranteed Result
Understand expected cost, why it does not guarantee success, and how to use target probability when planning random purchases.
Responsible Collecting Budget Guide
A practical guide to setting a budget for gacha pulls, blind boxes, random boosters, and prize tickets before buying.
Calculator Methodology
Review the formulas, assumptions, limitations, and editorial approach used by PrizeOdds Calculator.