Import a game and let a world-class engine reveal the best moves and your mistakes - then train with puzzles or play a human-like bot to put it into practice.
Analyze a gameWhether you want to review a game, train your tactics, or take on a human-like bot - it's all here.
Import any game and step through it with live Stockfish evaluation and best-move arrows on every position.
Sharpen your tactics with an endless stream of rated puzzles drawn from real games.
Take on a bot that plays like a real human at the rating you choose, then analyze the result instantly.
Powerful analysis tools that turn raw engine output into insight you can actually use.
Color-coded arrows draw the best moves straight onto the board, ranked by the engine.
Accuracy for both players, brilliant moves marked in teal, and every best move, inaccuracy, mistake and blunder.
See how often each opening move is played and the win, draw and loss rates behind it.
Quiz yourself against the engine's choice and find out instantly whether you'd have found it.
Visualize every candidate move and its evaluation at once to see the whole tactical picture.
Rated tactical puzzles from real games, ready whenever you want a quick training session.
Work through interactive chess puzzles drawn from real games to build pattern recognition and calculation. Stuck on one? Open it on the analysis board in a single click. Or take on the daily chess puzzles: an easy, a medium and a hard one each day, the same for everyone, each with its own streak to keep.
Solve puzzles now · Today's daily chess puzzle
Put what you've learned into practice against a bot that plays like a real person at the rating you choose - not a flawless engine. When the game is over, send it straight to the analysis board to see where it was won or lost.
Guides to the openings you keep meeting and the tactics that decide your games - each one linked to the board so you can try it immediately.
The Sicilian, French, Ruy Lopez, Queen's Gambit, London System and more - what each one is trying to do and the plans that follow.
Forks, pins, skewers, discovered attacks, back rank mates - learn the pattern, then drill it on endless rated puzzles.
Paste a game from Chess.com, Lichess or a PGN and find the move that actually lost it.
No account needed, nothing to download. Open the board and start analyzing in seconds - completely free.
Yes. The analysis board, the Stockfish engine, the opening explorer, the puzzles and the bots are all free to use, with no account and nothing to install. There is a paid tier for heavier use, but nothing described on this page requires it.
No. Open the board and start analyzing. An account is only useful if you want your games saved across devices.
Stockfish - the strongest open-source chess engine - compiled to WebAssembly so it runs inside your browser rather than on a shared server. Nothing is queued behind other users, and your positions stay on your device.
Yes. Paste the game's link from Chess.com or Lichess, or its PGN, and run the free game review: every move is graded against Stockfish, with each inaccuracy, mistake and blunder marked for both sides. No password or account linking is needed.
Yes. Everything runs in the browser, so it works on phones and tablets as well as desktops - including on machines where you cannot install software.
Turn the board so each player has a light square in the bottom-right corner. The rooks go in the corners, then the knights, then the bishops, with the queen on her own color and the king beside her; the pawns fill the rank in front. The chess board setup guide shows it square by square next to a board, and its editor sets up any other position to analyze or play.