Diagnostic report · your most recent games
Find the one mistake pattern
costing you rating points.
Not a dashboard. A diagnosis — Stockfish reads your recent chess.com games, isolates your most expensive recurring error, and shows the evidence.
Free · no account. Analysis runs in your browser — your games never touch our servers.
How the instrument works
Import
Your public game history streams in from the chess.com API — from a quick 50-game read to your entire recent history, your call. Cached locally, so re-scans are instant.
Engine pass
A pool of Stockfish 18 engines runs in your browser tab. Every move is screened; every significant eval swing is re-searched deeper and classified into a mistake taxonomy: hung pieces, ignored threats, missed tactics, bad trades, thrown wins.
Diagnosis
Mistakes are clustered across games by type, phase, opening and clock state, ranked by total win-probability lost. Recurrence matters, not drama. The top cluster is your leak — with exhibits from your real games and a prescription.
METHOD — Stockfish 18 (WASM) · adaptive two-pass search · mistakes = ≥10 win-probability points lost · clusters ranked by cumulative expected score lost · engine verdicts are ground truth; the written report only explains them. Not affiliated with chess.com.