Rules of chess


The rules of chess govern the play of the game of chess. Chess is a two-player abstract strategy board game. Each player controls sixteen pieces of six types on a chessboard. Each type of piece moves in a distinct way. The object of the game is to checkmate the opponent's king; checkmate occurs when a king is threatened with capture and has no escape. A game can end in various ways besides checkmate: a player can [|resign], and there are several ways a game can end in a draw.
While the exact origins of chess are unclear, modern rules first took form during the Middle Ages. The rules continued to be slightly modified until the early 19th century, when they reached essentially their current form. The rules also varied somewhat from region to region. Today, the standard rules are set by FIDE, the international governing body for chess. Slight modifications are made by some national organizations for their own purposes. There are variations of the rules for fast chess, correspondence chess, online chess, and Chess960.
Besides the basic moves of the pieces, rules also govern the equipment used, time control, conduct and ethics of players, accommodations for physically challenged players, and recording of moves using chess notation. Procedures for resolving irregularities that can occur during a game are provided as well.

Initial setup

Chess is played on a chessboard, a square board divided into a grid of 64 squares of alternating color. Regardless of the actual colors of the board, the lighter-colored squares are called "light" or "white", and the darker-colored squares are called "dark" or "black". Sixteen "white" and sixteen "black" pieces are placed on the board at the beginning of the game. The board is placed so that a white square is in each player's near-right corner. Horizontal rows are called ', and vertical columns are called '.
Each player controls sixteen pieces:
PieceKingQueenRookBishopKnightPawn
Number of pieces112228
Symbols






At the beginning of the game, the pieces are arranged as shown in the diagram: for each side one king, one queen, two rooks, two bishops, two knights, and eight pawns. The pieces are placed, one per square, as follows:
  • Rooks are placed on the outside corners, right and left edge.
  • Knights are placed immediately inside of the rooks.
  • Bishops are placed immediately inside of the knights.
  • The queen is placed on the central square of the same color of that of the piece: white queen on the white square and black queen on the black square.
  • The king takes the vacant spot next to the queen.
  • Pawns are placed one square in front of all of the other pieces.
Popular mnemonics used to remember the setup are "queen on her own color" and "white on right". The latter refers to setting up the board so that the square closest to each player's right is white.

Gameplay

White and black

The player controlling the white pieces is named "White"; the player controlling the black pieces is named "Black". White moves first, then players alternate moves. Making a move is required; it is not legal to skip a move, even when having to move is detrimental. Play continues until a king is checkmated, a player [|resigns], or a draw is declared, as explained below. In addition, if the game is being played under a time control, a player who exceeds the [|time limit] loses the game unless they cannot be checkmated.
The official chess rules do not include a procedure for determining who plays White. Instead, this decision is left open to tournament-specific rules or, in the case of casual play, mutual agreement, in which case some kind of random choice such as flipping a coin can be employed. A common method is for one player to conceal a pawn of each color in either hand; the other player chooses a hand to open and receives the color of the piece that is revealed.

Movement

Basic moves

Each type of chess piece has its own method of movement. A piece moves to a vacant square except when an opponent's piece.
Except for any move of the knight and [|castling], pieces cannot jump over other pieces. A piece is captured when an attacking enemy piece replaces it on its square. The captured piece is thereby permanently removed from the game. The king can be put in check but cannot be captured.
  • The king moves exactly one square adjacent to it. A special move with the king known as castling is allowed only once per player, per game.
  • A rook moves any number of vacant squares horizontally or vertically. It also is moved when castling.
  • A bishop moves any number of vacant squares diagonally.
  • The queen moves any number of vacant squares horizontally, vertically, or diagonally.
  • A knight moves to one of the nearest squares not on the same,, or. The knight is not blocked by other pieces; it jumps to the new location.
  • Pawns have the most complex rules of movement:

    Castling

Castling consists of moving the king two squares towards a rook, then placing the rook on the other side of the king, adjacent to it. Castling is only permissible if all of the following conditions hold:
  • The king and rook involved in castling must not have previously moved;
  • There must be no pieces between the king and the rook;
  • The king may not currently be under attack, nor may the king pass through or end up in a square that is under attack by an enemy piece ;
  • The castling rook must be on the same rank as the king
An unmoved king and an unmoved rook of the same color on the same rank are said to have castling rights.

''En passant''

When a pawn advances two squares on its initial move and ends the turn adjacent to an enemy pawn on the same, it may be captured en passant by the enemy pawn as if it had moved only one square. This capture is legal only on the move immediately following the pawn's advance. The diagrams demonstrate an instance of this: if the white pawn moves from a2 to a4, the black pawn on b4 can capture it en passant, moving from b4 to a3, and the white pawn on a4 is removed from the board.

Promotion

If a player advances a pawn to its eighth rank, the pawn is then promoted to a queen, rook, bishop, or knight of the same color at the choice of the player. The choice is not limited to previously pieces. Hence it is theoretically possible for a player to have up to nine queens or up to ten rooks, bishops, or knights if all of the player's pawns are promoted.

Check

A king is in check when it is under attack by at least one enemy piece. A piece unable to move because it would place its own king in check may still deliver check to the opposing player.
It is illegal to make a move that places or leaves one's king in check. The possible ways to get out of check are:
  • the king to a square where it is not in check.
  • the checking piece.
  • a piece between the king and the opponent's threatening piece.
In informal games, it is customary to announce "check" when making a move that puts the opponent's king in check. In formal competitions, however, check is rarely announced.

End of the game

Checkmate

If a player's king is placed in check and there is no legal move that player can make to escape check, then the king is said to be checkmated, the game ends, and that player loses. Unlike the other pieces, the king is never captured.
The diagram shows an example checkmate position. The white king is threatened by the black queen; the empty square to which the king could move is also threatened; and the king cannot capture the queen, because it would then be in check by the rook.

Resigning

Either player may resign at any time, conceding the game to the opponent. To indicate resignation, the player may say "I resign". Tipping over the king also indicates resignation, but it should be distinguished from accidentally knocking the king over. Stopping both clocks is not an indication of resigning, since clocks can be stopped to call the arbiter. An offer of a handshake is sometimes used, but it could be mistaken for a draw offer.
Under FIDE Laws, a resignation by one player results in a draw if their opponent has no way to checkmate them via any series of legal moves, or a loss by that player otherwise.

Draws

The game ends in a draw if any of these conditions occur:
  • The player to move is not in check and has no legal move. This situation is called a stalemate. An example of such a position is shown in the adjacent diagram.
  • The game reaches a dead position.
  • Both players agree to a draw after one of the players makes such an offer.
In addition, in the FIDE rules, if a player has run out of time, or has resigned, but the position is such that there is no way for the opponent to give checkmate by any series of legal moves, the game is a draw.
[|FIDE's competitive rules of play] allow a player to claim a draw in either of two situations:
  • Fifty moves have been made by each player without a capture or pawn movement ;
  • The same position has appeared three times ; this is the threefold repetition rule.
These rules help prevent games from being extended indefinitely in tournaments.
There is no longer a rule specifically defining perpetual check as a draw. In such a situation, either the threefold repetition rule or the fifty-move rule will eventually come into effect. More often, the players will simply agree to a draw.
Dead position
A dead position is defined as a position where neither player can checkmate their opponent's king by any sequence of legal moves. According to the rules of chess the game is immediately terminated the moment a dead position appears on the board.
Some basic endings are always dead positions; for example:
  • king against king;
  • king against king and bishop;
  • king against king and knight.
Blocked positions can arise in which progress is impossible for either side, such as the diagrammed position; these too are dead positions.
USCF rules, for games played under a time control that does not include delay or increment, allow draw claims for "insufficient losing chances". For example, if each player has only a king and a knight, checkmate is only achievable with the co-operation of both players, even if it is not a dead position.