📖 Overview
Use this calculator to evaluate deck consistency and opening hand reliability for board game card systems.
🧪 Example Scenarios
Use these default and higher-pressure example inputs to explore how sensitive this calculator is before using your real numbers.
| Input | Base Case | Higher Pressure Case |
|---|---|---|
| Desired Cards In Deck | 8 | 9.2 |
| Total Deck Size | 60 | 69 |
| Cards Drawn | 10 | 11.5 |
| Desired Hits Needed | 1 | 1.15 |
⚙️ How It Works
Uses a hypergeometric model to estimate the probability of drawing at least a target number of desired cards without replacement.
The Formula
P(X ≥ k) = Σ [ C(K,i) × C(N−K, n−i) ] / C(N,n), for i = k..min(K,n)
| N | Total deck size |
| K | Desired cards in deck |
| n | Cards drawn |
| k | Minimum desired hits needed |
💡This is the standard card-draw probability model used for TCGs and deck builders when cards are drawn without replacement.
Quick Reference
| Deck setup | Draw target | Probability |
|---|---|---|
| 8 targets in 60-card deck | At least 1 in 7 draws | ~65.34% |
| 8 targets in 60-card deck | At least 2 in 10 draws | ~24.19% |
| 12 targets in 40-card deck | At least 1 in 5 draws | ~85.10% |
| 6 targets in 50-card deck | At least 1 in 6 draws | ~55.73% |
When To Use This
- Use this tool when you need a fast decision during active planning or execution.
- Use this before committing money, time, or tradeoffs that are hard to reverse.
- Use this to compare options using the same assumptions across scenarios.
Edge Cases To Watch
- Results can be misleading if key inputs are missing, stale, or unrealistic.
- Very small or very large values may amplify rounding effects and interpretation risk.
- If assumptions change mid-decision, recalculate before acting.
Practical Tips
💡 Lower deck size or higher target-card count strongly increases hit odds.
💡 Use this to compare consistency before finalizing deck lists.
💡 Run a best-case, base-case, and worst-case scenario before deciding.
💡 Use recent real values, not ideal assumptions, for better accuracy.
Frequently Asked Questions
❓ Why not use simple percentage?
Simple percentage ignores no-replacement effects and is less accurate for card draws.
❓ Can required hits exceed cards drawn?
No, required hits must be less than or equal to cards drawn.