Chess

Goal

Chess is a strategy game for two sides, White and Black, on an 8×8 board. The goal is to checkmate the enemy king: attack it so that it has no way to escape. Play against the computer at three levels — Easy, Medium and Hard, as White or Black — or play with a friend on the same device. White always moves first.

Controls

• Computer: click one of your pieces and dots appear on every square it may move to; then click the destination. You can also drag a piece with the mouse and drop it. Press U (or Ctrl+Z) to undo and F to flip the board.
• Phone: tap a piece, then tap where it should go — or press and drag it with your finger and let go on the target square. Small dots mark empty squares; large rings mark enemy pieces you can capture.
• Pale yellow squares show the last move. A king in check glows red.
• Buttons below the board: Undo (against the AI it takes back both your move and its reply), Flip board, Offer draw, Resign and sound on/off.
• An unfinished game is saved automatically and continues the next time you open the page.

Special rules

• Castling: the king moves two squares towards a rook and the rook jumps to the other side of it. Allowed only if neither piece has moved, the squares between them are empty, and the king is not in check and does not pass through or land on an attacked square. To castle, select the king and pick the square two steps away.
• En passant: when an enemy pawn advances two squares and lands right beside your pawn, you may capture it as if it had moved only one square — but only on the very next move.
• Promotion: a pawn reaching the last rank becomes a Queen, Rook, Bishop or Knight of your choice.
• Draws: stalemate (no legal move but not in check), 50 moves without a capture or pawn move, the same position three times, not enough material to mate, or a draw by agreement.

Tips

• In the opening, push a centre pawn, develop your knights and bishops early, then castle to keep your king safe.
• Before every move, check what your opponent’s last move is threatening.
• New to chess? Start on Easy — and if you slip, just press Undo and try again.