Private, browser-local utility
Mastermind Solver
Filter possible Mastermind codes from guesses and exact-position or misplaced-color feedback.
One line per guess: CODE exact misplaced. Example: ABCD 1 2.
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Candidate codes
Feedback and search method
V1 supports length 3–5, 4–8 symbols, and optional repeats, capped at 10,000 possible codes. Feedback counts exact positions first, then matches remaining symbol frequencies so duplicates are never double-counted. Every history row filters the complete bounded candidate set.
The displayed next code is a deterministic remaining candidate, not an optimal-play claim. No remote solver is used.