About
Free game review, and the rest of the club
Chess Review started as one thing: chess.com charges for Game Review, and the analysis itself, Stockfish, is free software. So this runs Stockfish in your browser, on your own games, with no paywall and no daily limit. Then it grew a Play mode, puzzles, training drills, lessons and leaderboards, all on the same terms.
How it works
The engine does the chess and a language model does the writing, never the other way round. Stockfish decides what was good, what was bad, and what should have been played. If you add a free OpenRouter key, a model is handed those facts and asked to explain them in plain English; it is told, in every prompt, not to calculate or invent moves. Without a key everything still works except the written coaching and lessons.
In Play, the same split holds: Stockfish sets the strength on a ladder from 800 to 3200, and a model, if you pick one, chooses among the moves the engine allows at that rating and says why. It cannot make the opponent stronger or weaker than the label.
What it is built on
Stockfish 19 (GPL), compiled to WebAssembly, single-threaded so it runs on any host. chess.js for rules. chess.com's public API for games, statistics, the daily puzzle and leaderboards, with no key required. Lichess's puzzle API and open puzzle database (CC0) for rated tactics and Learn examples. lichess-org/chess-openings (CC0) for opening names and book-move detection. Piece sets from Lichess, restricted to permissive licences: cburnett and merida (GPLv2+), chessnut (Apache 2.0), kiwen-suwi (CC BY 4.0), fantasy (MIT), rhosgfx (CC0). The interface follows Apple's Human Interface Guidelines, with colours and type taken from the macOS 27 and iOS 27 UI kits; the app icon uses the squircle from Apple's icon template.
Who made it
Built by Pratik Patel. Follow along on X. If it saved you a subscription, sponsoring on GitHub keeps it free for everyone else.
Not affiliated
Chess Review is an independent project. It is not affiliated with, endorsed by, or connected to chess.com, Lichess, OpenRouter, Netlify or Apple. chess.com, Lichess and other names are trademarks of their respective owners and are used only to describe where data comes from.
Terms, briefly
The app is provided as-is, free of charge, with no warranty. Engine evaluations, accuracy figures and model-written text are for study and may be wrong; the accuracy number in particular is computed independently and runs a few points more generous than chess.com's own. Use chess.com's and Lichess's services in line with their terms. Your OpenRouter usage is subject to OpenRouter's terms and any costs on your account.