Mode
Casual (1000) · you play White
White to move
No moves yet.
Top 10
How to play
- Pick a level and which colour you want, then move to start the game.
- Click a piece to pick it up — every square it can legally reach lights up — then click one of them. Dragging works too; both go through the same rules.
- The computer replies automatically. Undo takes back your move and its reply.
- Beat it and your number of moves goes on that level's leaderboard.
- When it is over the board stays put. Analyse lets you play both sides from the final position and see what the engine thinks of every move.
- The strips above and below the board are what each side has captured, with the material edge if there is one.
- Full rules: castling, en passant, promotion, stalemate, threefold repetition, the fifty-move rule and dead positions.
- A level's number is the rating it plays at, roughly: Casual (1000) is about a 1000-rated club player.
- Moves come from Stockfish, running in your browser rather than on a server. It downloads once, about 2 MB, the first time the computer has to move.
- Lower levels mix in random legal moves — Stockfish is far too strong otherwise, even at its shallowest.
- Only a win records a score, and it is the number of moves you took, lowest first.
- Analysis scores every legal move one at a time, so the list fills in over a second or two. It only runs after a game — it can never help you mid-game. Tutorial mode is where you get it while you play.
Debug log
Nothing yet. Engine moves and scoring passes are logged here as they happen, with how long each search took.