Diagnostic report · your most recent games
Find the one mistake pattern
quietly costing you games.
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, its refutation line replayed, and the mistake matched to a specific motif: back-rank mates, knight forks, queen raids, pins, skewers, hung pieces.
Diagnosis
Motifs are clustered across games and ranked — recurrence and how far you deviate from your rating band matter, not drama. The most persistent pattern is your diagnosis, weighed against your peers, with exhibits from your real games, how you actually lose, 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.