Chess

The aim of the game

Each player tries to checkmate the other king. A king is in check when an enemy piece attacks it, and checkmate means it is in check with no way out: it can't move to safety, the attacker can't be captured, and the line of attack can't be blocked. The king itself is never actually taken off the board.

How the pieces move

• King: one square in any direction. It may never move onto an attacked square.
• Queen: any distance along a rank, file or diagonal. It is the strongest piece.
• Rook: any distance along a rank or file.
• Bishop: any distance along a diagonal, so it stays on one square color all game.
• Knight: an L shape, two squares one way and one square to the side. It is the only piece that can jump over others.
• Pawn: one square straight ahead, or two from its starting square. Unlike every other piece, it captures differently from how it moves: one square diagonally forward.

Chess rules

• White moves first, then the players take turns. Passing is not allowed.
• A piece captures by moving onto an enemy piece's square. Only the knight can pass over other pieces.
• You may never make a move that leaves your own king in check.
• Castling moves the king two squares toward a rook, and the rook hops over to the king's other side. Neither piece may have moved before, the squares between them must be empty, and the king may not be in check, pass through an attacked square or land on one. The rook is allowed to pass through an attacked square.
• En passant: when a pawn moves two squares and lands beside an enemy pawn, that pawn may capture it as though it had moved only one. This is allowed only on the very next move.
• Promotion: a pawn that reaches the far side of the board must become a queen, rook, bishop or knight of your choice, even if you still have that piece.

How a game can be drawn

• Stalemate: the player to move has no legal move and is not in check.
• Not enough pieces: neither side can ever give mate, as with king against king, or king and bishop or king and knight against king. The game ends at once.
• Threefold repetition: when the same position comes up for the third time, with the same player to move and the same castling and en passant options, the player to move can claim a draw. They can also claim it with the move that is about to repeat the position.
• The fifty-move rule: after fifty moves by each side with no capture and no pawn move, the player to move can claim a draw.
• Automatic draws: if nobody claims, the game is drawn anyway at the fifth appearance of a position, or after seventy-five moves by each side with no capture or pawn move.

How to play on this page

1. Open Setup and choose your opponent: the computer, a friend online, or 2 players, one device.
2. Against the computer, pick one of six levels, from Novice to Hard, and whether you play White or Black. Each level shows its approximate rating. If you play Black, the board turns round so that your pieces are at the bottom. Random draws your color afresh for each new game.
3. Tap a piece and then a square, or drag the piece there. A dot marks each square it can move to, and a red ring marks anything it can capture.
4. When a pawn promotes, choose its new piece from the list that opens on the board.
5. Use Undo to take a move back. Resign and Claim draw are under More. Your settings, score and the game in progress are saved in this browser.
6. Tap any move in the list to see the board as it was then, and use the arrows to step through the game. On a keyboard, Left and Right do the same while the list has focus. You can't play on an earlier position, so Back to game returns you to the live one. When a game ends, Review game lets you go back over it.
7. Stuck? Hint draws one good move on the board. To measure your progress, turn on Rated game in Setup: a rated game has no Undo and no hints, and leaving one partway counts as a loss.

Reading the move list

The moves are written in standard algebraic notation. Each square has a name made of its file and rank, such as e4. Pieces go by a capital letter: K for king, Q for queen, R for rook, B for bishop and N for knight. Pawns have no letter, so Nf3 is a knight moving to f3 and e4 is a pawn moving to e4.

An x marks a capture, as in Bxc6. O-O means castling on the king's side and O-O-O on the queen's side. A + marks check, # marks checkmate, and =Q shows a pawn promoting to a queen.

Tips for playing better

• Before every move, ask what your opponent's last move threatens. Most games between beginners are lost to a piece left hanging, not to a deep plan.
• In the opening, control the center with a pawn or two, bring out your knights and bishops, and castle early so that your king is safe.
• Don't move the same piece twice in the opening without a good reason, and don't bring your queen out too soon, because it will just be chased around.
• Learn the basic values: a pawn is worth 1, a knight or bishop 3, a rook 5 and a queen 9. When trading pieces, count before you capture.
• Look for forks and pins. A knight attacking two pieces at once, or a bishop pinning a piece to the king, often wins material by force.
• When you are ahead, trade pieces rather than pawns. In the endgame, bring your king into the fight, because it is suddenly a strong piece.

A new chess puzzle every day

Choose Daily puzzle to solve one position a day, the same for everyone, with a new one at midnight UTC. It may be a mate in one, two or three, or a fork, pin, skewer, discovered attack or winning exchange. Every puzzle is made and checked with our own engine. The line above the board says what to aim for, the other side's replies play themselves, and a wrong move is taken back so you can try again. Your streak is kept in this browser, and puzzles never change your rating or your score against the computer.

Frequently asked questions

Can I play chess here without signing up?

Yes. The whole game runs in your browser on a computer, tablet or phone, with nothing to download and no account to create.

How strong is the computer?

There are six levels. Novice misjudges positions and sometimes even misses a mate in one, so it is a good place to learn. Each level above it looks further ahead and judges positions better. We measured them in matches against a strong open-source chess program set to known strengths, and Setup shows the result beside each level: from about 700 to about 2300. These numbers are estimates from matches between programs, not from games against people, so a rating on another site can differ. The lowest levels are the least certain, because that program can't be set any weaker. Only Hard depends on your device: it thinks for a fixed time, so it plays stronger on a fast computer than on a slower device, and the figure shown is the lower one. The computer uses its own search and doesn't rely on an opening book, so its games vary.

What is the rating in Setup?

It is an estimate of your strength, worked out from rated games against this computer. It is marked provisional for your first 15 games, and it can't climb far above the level you are beating, so beating Novice over and over won't inflate it. It is kept only in this browser, where it could be edited, so it is a personal measure of progress and not an official chess rating.

Can two people play on one device?

Yes. In Setup, choose "2 players, one device" and take turns on the same screen. You can also turn on "Turn the board after each move", so that whoever is to move sees their own pieces at the bottom.

Why can't I castle right now?

Castling isn't available if your king or that rook has already moved, if a piece stands between them, or if your king is in check, would pass through an attacked square or would land on one. Moving the king or rook away and back doesn't bring the right back.

What is en passant?

It is a special pawn capture. If an enemy pawn moves two squares from its starting square and lands right beside your pawn, you can capture it as if it had moved only one square. You must do it on the very next move, or the chance is gone. A red ring on the board shows when it is possible.

What is the difference between stalemate and checkmate?

In both cases the player to move has no legal move. If their king is in check it is checkmate and they lose. If it isn't in check it is stalemate and the game is a draw, which is how a player far behind can sometimes save the game.

Why does the Claim draw button stay gray?

A draw can only be claimed when the same position is about to appear, or has appeared, for the third time, or after fifty moves by each side with no capture or pawn move. When you can claim one, the button lights up and the line above the board tells you so. You can also just keep playing if you think you can win.

Will my game and score be saved?

Yes. Your settings, your score and the game in progress are saved in this browser, so they will still be here when you come back. They are not sent anywhere, and clearing your browser data removes them.

How does the daily puzzle work?

Choose Daily puzzle on the chess page; it is also under More and in Setup. Everyone gets the same position that day, and a new one arrives at midnight UTC, which the page shows in your local time. A hint shows the piece to move and then the move, and your result says how many tries you took and whether you used a hint. Afterwards you can step through the solution and share a result that gives nothing away. A game you are playing stays saved while you solve it.