Frequently asked questions

Audit Chess is a free chess analysis site with 29 tools built from your own Lichess or Chess.com games: Stockfish game review with accuracy by phase, an engine-checked AI move explainer, Deep Analysis (an optional, more thorough re-check of all your games), puzzles from your own blunders, an adaptive puzzle trainer, mistake themes (your errors ranked by tactic, positional weakness, endgame rule and pawn structure), an opening tree, opening weaknesses, a repertoire builder, opening traps, an endgame profile, blown wins, missed mates, your brilliant (!!) moves, a 40+ metric playstyle profile, activity insights, period reports, opponent scouting, Rival, a bot that plays your opponent’s real openings, training missions, daily goals, Chess Wrapped (your year in review), play on Lichess with instant review, game links (put auditchess.com in front of a Chess.com or Lichess game URL), leaderboards, and four free trainers: Chess Basics, Coordinate Trainer, Knightdoku and Practice. No account needed; the analysis runs in your browser.

Because it is two tools in one and free without limits: every game gets an unlimited move-by-move Stockfish review with engine-checked explanations, and your whole Lichess or Chess.com history is analyzed at once for the openings, mistake themes and blown wins that cost you rating. It turns your own blunders into puzzles, needs no account, keeps your games private in your browser, and includes 29 tools from opponent scouting and the Rival bot to a repertoire builder.

Enter your Lichess or Chess.com username in Audit Chess and it reviews every game move by move with Stockfish - an accuracy score, an eval graph, and every inaccuracy, mistake and blunder - then turns your mistakes into puzzles. It runs in your browser, free, with no account.

Study your own games instead of generic theory. Audit Chess ranks every opening you play by result, flags the lines quietly costing you points, profiles your endgames and playstyle, and shows the winning positions you throw away - so you know exactly what to drill.

Yes. Audit Chess replays every blunder and missed tactic from your real games as a solvable puzzle, and verifies each solution live, move by move, with Stockfish. You drill your own recurring mistakes rather than random positions.

The fastest gains come from your own games: find the openings you score worst in, the mistakes you repeat, and the winning positions you let slip, then drill exactly those. Audit Chess does this automatically from your Lichess or Chess.com history.

Yes. Enter an opponent's Lichess or Chess.com username and Audit Chess surfaces their weakest openings and the exact lines to prepare against them, matched to your own repertoire. You can then rehearse on the Rival page against a bot that plays their real openings.

Yes, it is free, and no account is required. Analysis runs entirely in your browser - nothing is uploaded and no sign-up is needed.

Yes. Audit Chess analyzes game histories from both Chess.com and Lichess.

Audit Chess gives you the same kind of move-by-move review of a single game - every move graded Brilliant to Blunder, accuracy, eval graph, plus engine-checked explanations - free and unlimited. On top of that it analyzes your whole history at once and finds patterns across it: your worst openings, repeated blunders by theme, blown wins and endgame gaps, then turns them into puzzles. It's free, needs no account, and runs on your device.

Enter your Lichess or Chess.com username, or switch to Upload PGN and paste a single game. Stockfish runs a full move-by-move review in your browser: an accuracy score for each side, an evaluation graph, and a label on every move from Brilliant to Blunder. It is free, needs no account, and nothing is uploaded.

On Chess.com open a game, choose Share, then PGN and copy it. On Lichess open a game and use the PGN download or the "FEN & PGN" panel. Paste that text into the Upload PGN box, or upload a .pgn file.

It measures how closely your moves match Stockfish's best play, as a 0–100 score based on how much winning chance each move gave up. Typical club players score between 70 and 85.

No. Games are fetched from the Lichess/Chess.com API and analyzed entirely in your browser - your games are never stored on our servers. If you create an optional account, we store only what it needs to sync across devices: your chess handle, saved repertoire, puzzle rating and daily goals.

No. Audit Chess runs in your web browser. There is nothing to download or install and no account to create.

It analyzes around 1,000 games in under a minute and scales to about 5,000.

No. Audit Chess is an independent tool that reads public game histories from Chess.com and Lichess. It is not affiliated with or endorsed by either.

Yes. Switch the input to PGN and upload or paste any standard PGN file - from an over-the-board tournament, another site, or a database export. Audit Chess lists every player in the file so you can pick which one is you, then analyzes those games exactly like a username import.

On any game in the Review tab, "Explain game" writes a short plain-English coach note on each key moment - why a move was strong or a mistake, what the threat was, and what was better. Every note is built from facts Stockfish has already verified, so the explanation never invents a tactic the engine did not find.

Everything works without one. An optional free account remembers your chess handle, syncs your saved opening repertoire and puzzle rating across devices, and unlocks Leaderboards and Daily Goals - a small daily plan of games, reviews, puzzles and repertoire drills with a streak to keep going.

Yes, Lichess games. On the Play page, connect your Lichess account and play real rated or casual Lichess games on the Audit Chess board, then review each game the moment it ends. Rated games count toward your real Lichess rating. While a game is live, the engine and analysis are switched off in every Audit Chess tab, as Lichess fair-play rules require.

Yes. On the Rival page, enter your next opponent's Lichess or Chess.com username and play a bot built from their public games: it plays the openings they actually play, as often as they play them, then continues at roughly their rating once you leave their book.

Change chess.com to auditchess.com in the game link (for example auditchess.com/game/live/123456789), or for Lichess go to auditchess.com/lichess/ followed by the game id. The game opens straight in Game Review.

Yes. Alongside game analysis there are free beginner trainers: Chess Basics teaches how every piece moves, the Coordinate Trainer drills the 64 squares against a 30-second clock, Practice lets you play out basic checkmates and essential endgames against Stockfish, and Knightdoku trains board vision.

Yes - it runs in any modern mobile browser with nothing to install. Because Stockfish runs on your own device, analyzing a large game history is slower on a phone than on a laptop; for big imports a computer is faster, and results are cached so you only wait once.