How do I use the Gacha Simulator?

Enter the required values and the Gacha Simulator will instantly calculate and display the result. No registration required.

Is the Gacha Simulator free?

Yes, all tools on CalcBOX are completely free with no registration required.

All calculations are performed in your browser. No data is sent to any server.

🎰

Gacha Simulator

Simulate gacha pulls with custom rates. Pity system & probability graph.

🎮 Game / Preset

* Genshin: SSR 0.6% / soft pity from 74 / hard pity 90 | FGO: SSR 1% | Blue Archive: SSR 3% / hard pity 200 | Uma Musume: SSR 3%

⚙️ Gacha Settings

Drop Rates

SSR (%)%

SR (%)%

R (%)%

N (auto)

0.00%

Pity System

Hard Pity – guaranteed SSR at:

pulls

Soft Pity – rate increases near pity

Activate from pull #

Extra % per pull

Cost / Pullyen

Pity: 0 / 90 pulls

📊 Statistics

Total Pulls

SSR Count

Actual Rate

¥0

Total Cost

Expected pulls / SSR166.7 pulls

Expected cost / SSR¥26,667

Prob. in 10 pulls5.84%

Prob. in 100 pulls45.22%

Prob. by pity41.82%

🧮 Budget / Target Calculator

Budgetyen

Pulls

0.37

Expected SSRs

31.1%

P(≥1 SSR)

📈 Cumulative Probability

P(at least 1 SSR within N pulls) at 0.6% rate

About Gacha Simulator

Simulate gacha pulls with fully customizable SSR/SR/R/N rates, hard pity, and soft pity. Game presets (Genshin-like, FGO, Blue Archive, Uma Musume) included. The budget calculator shows expected SSRs and probability for a given budget, while the target calculator shows pulls and cost needed to reach a desired SSR count.

Formula: P(≥1 SSR in N pulls) = 1 − (1 − rate)^N. Target cost uses negative binomial approximation.

📖How to Use

1Set rarity tiers and drop rates
2Specify the number of pulls
3See the resulting probability distribution and expected cost

💡Tips & Knowledge

•With a 1% rate, after 100 pulls there's still only a 63.4% chance you've gotten the item (1 − 0.99¹⁰⁰)
•Pity systems guarantee a drop every N pulls. True cost = pity count × cost per pull
•Mean and median are different. Be cautious about "average pulls" figures advertised by games

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All calculations run in your browser. No data is sent to any server.