Why a separate "hand probability" lab?
Yu-Gi-Oh's 40-card minimum and the 5-card opening hand make every percentage point matter more than in 60-card formats. Most generic calculators assume MTG-style numbers; ours uses your real deck size.
The Yu-Gi-Oh! community already has plenty of fan sites. These tools cover three things most of them get wrong: probability that respects the 40-card minimum (not 60), a format validator that distinguishes "needs review" from "definitely illegal," and a tribute/synchro/xyz advisor that respects current summoning mechanics.
Yu-Gi-Oh! is hypergeometric, not intuition. Most deck-builders wildly misjudge the chance of opening their 1-of "going-second" handtrap. This lab takes your deck size, the card's copies, and the minimum you want in your opening 5 — and returns exact probabilities for "see it in opening hand" and "see it within first 10 cards".
Whisper-quiet "extras": we also compute how often you'll see exactly 0, exactly 1, exactly 2+ copies, which matters for handtraps and "bricks".
Paste a deck list and the tool counts Main/Extra/Side, flags any card with more than 3 copies, and gives a summary per monster / spell / trap type. We do not maintain a private banlist; the tool simply marks cards that need human review against the official Konami list.
Pick the monster you want to summon; the tool enumerates the tribute combinations from your hand / field: 1 tribute of ≥ level 5 → level 5-6, 2 tributes ≥ level 7 → level 7-8, plus Tuner + non-Tuner combinations for Synchro and 2+ level-4s for Xyz. A fast visual sanity check before you commit.
Yu-Gi-Oh's 40-card minimum and the 5-card opening hand make every percentage point matter more than in 60-card formats. Most generic calculators assume MTG-style numbers; ours uses your real deck size.
Konami changes the list every 3 months. Catching up reliably would mean a paid database — and stale lists are worse than no list. We mark cards that need review against the official source.
Ritual, Pendulum, and Link are still in active flux. The tool covers the three most stable mechanics: tribute, Synchro, Xyz.
Yes — the probability lab uses the closed-form hypergeometric formula, not Monte-Carlo. Even at 10⁷ trials a simulation would still carry ±0.05% noise.