Chess (FIDE) — Official Rules

The game of chess is played between two opponents who move their pieces alternately on a square board called a 'chessboard'. The player with the white pieces (designated home in Arena Metrics) commences the game; a player is said to 'have the move' when it is their turn to play. After the move of one player, it is the other player's move.

The objective of each player is to place the opponent's king 'under attack' in such a way that the opponent has no legal move. The player who achieves this is said to have checkmated the opponent's king and to have won the game. Leaving one's own king under attack, exposing one's own king to attack, or 'capturing' the opponent's king is not allowed. The opponent whose king has been checkmated has lost the game.

If the position is such that neither player can possibly checkmate the opponent's king, the game is drawn (a 'dead position'). The game is also drawn by stalemate, by agreement, by the threefold-repetition and fifty-move rules, and automatically by fivefold repetition or seventy-five moves without a pawn move or capture (see Chapter 9). The result of a drawn game is ½-½ (FIDE notation: 1/2-1/2).

The chessboard is composed of an 8 x 8 grid of 64 equal squares alternately light (the 'white' squares) and dark (the 'black' squares). The board is placed between the players so that the near corner square to the right of each player is white. The eight vertical columns are files, the eight horizontal rows are ranks, and a straight line of same-coloured squares touching corner to corner is a diagonal.

At the beginning of the game each player has 16 pieces: one king, one queen, two rooks, two bishops, two knights and eight pawns. One player controls the white pieces, the other the black pieces. In Arena Metrics, home = White and away = Black.

The pieces start on the two ranks nearest each player. On the back rank, from a player's left to right, stand: Rook, Knight, Bishop, Queen, King, Bishop, Knight, Rook. The eight pawns occupy the rank immediately in front. The rule 'queen on her own colour' applies: the white queen stands on a white square (d1) and the black queen on a black square (d8); the king occupies the remaining central square (e1 / e8).

No piece (except the knight, in castling, and a capture) can be moved over a square occupied by another piece. A piece moving to a square occupied by an opponent's piece captures it; the captured piece is removed from the board as part of the same move. A piece is said to attack an opponent's piece if it could capture it on that square, even if it is pinned to its own king.

The bishop may move to any square along a diagonal on which it stands. The rook may move to any square along the file or rank on which it stands. The queen combines both: it may move to any square along a file, rank or diagonal. None of these pieces may jump over an intervening piece of either colour.

The knight moves in an 'L' shape: to one of the squares nearest to that on which it stands but not on the same rank, file or diagonal. The knight is the only piece that jumps over intervening pieces. The king may move to any adjoining square (one square in any direction) that is not attacked by an opponent's piece, and may also move by castling (Article 3.5). A king is 'in check' if attacked by one or more of the opponent's pieces; a player may not make any move that places or leaves their own king in check.

The pawn moves forward to the unoccupied square immediately in front on the same file, or on its first move may advance two squares along the same file provided both are unoccupied. A pawn captures diagonally forward one square to either side. En passant: a pawn attacking a square crossed by an opponent's pawn that has just advanced two squares may capture that pawn as though it had moved only one square, but only on the immediately following move.

Castling is a move of the king and either rook of the same colour along the player's first rank, counting as a single king move. The king is transferred two squares towards the rook, then that rook is transferred to the square the king has just crossed. Castling is permanently illegal if the king has already moved, or with a rook that has already moved. Castling is temporarily prevented if the square the king starts on, crosses, or ends on is attacked, or if there is any piece between king and rook.

When a pawn reaches the rank furthest from its starting position (the eighth rank for white, the first for black), it must be exchanged, as part of the same move and on the same square, for a new queen, rook, bishop or knight of the same colour. The player's choice is not restricted to pieces previously captured, so a player may have, for example, two or more queens. This exchange is called promotion and the effect of the new piece is immediate.

Each move must be made with one hand only. When castling the player should first move the king with one hand and then the rook with the same hand. A move is completed when the player, having made it, presses the clock (or, in the last move of the game, when the result is determined).

Only the player having the move may adjust one or more pieces on their squares, provided that they first express the intention (for example by saying 'j'adoube' or 'I adjust'). Outside this declaration, touching a piece carries obligations under Article 4.3.

If the player having the move deliberately touches on the board one or more of their own pieces, they must move the first piece touched that can be moved. If they deliberately touch one or more of the opponent's pieces, they must capture the first piece touched that can be captured. If a player touches their king and a rook, they must castle on that side if it is legal; otherwise they must move the king (or, if the king cannot move, make another legal move). If no touched piece can be moved or captured, the player may make any legal move.

When, as a legal move or part of a legal move, a piece has been released on a square, it cannot be moved to another square on that move. The move is then determined. A draw offer is governed separately (see Chapter 9): a player may offer a draw only after making their move and before pressing the clock.

The game is won by the player who checkmates the opponent's king with a legal move; this immediately ends the game. The game is also won by the player whose opponent declares they resign; this immediately ends the game (unless the position is such that the winner could not checkmate by any series of legal moves, in which case the game is a draw).

The game is drawn when the player to move has no legal move and their king is not in check — this is stalemate — and ends the game immediately. The game is also drawn when a 'dead position' arises, i.e. when neither player can checkmate the opponent's king with any series of legal moves; this ends the game immediately, provided the move producing it was legal. A game may also be drawn by agreement once both players have made at least one move (see Chapter 9).

A win scores 1 point, a draw ½ point, and a loss 0 points for the player. In game-result notation a White win is recorded 1-0, a Black win 0-1, and a draw 1/2-1/2. The result is final once the game is completed by checkmate, stalemate, resignation, agreement, an automatic draw, or a loss on time or by penalty.

A 'chessclock' has two time displays connected so that only one runs at a time. Each player must make a number of moves (or all moves) in an allotted time, and may be given additional time before each move (an 'increment', 2-60 seconds). After making a move on the board, a player must press the clock with the same hand that moved the piece, stopping their own time and starting the opponent's. A player may stop both clocks only to seek the arbiter's assistance.

A 'flag-fall' occurs when the allotted time of a player has expired. Except where Articles 5.1, 5.2 (checkmate, stalemate, dead position, etc.) apply, a player who does not complete the prescribed number of moves in the allotted time loses the game. However, the game is drawn if the position is such that the opponent cannot checkmate the player's king by any possible series of legal moves. A flag is considered to have fallen when the arbiter observes it or when a valid claim is made.

FIDE classifies over-the-board games by thinking time. Standard ('classical') play is where each player's thinking time is at least 60 minutes. Rapid is more than 10 but less than 60 minutes (time plus 60 x increment). Blitz is 10 minutes or less (time plus 60 x increment). A common classical world-level control is 90 minutes for the first 40 moves, then 30 minutes for the rest, with a 30-second increment from move one. Late arrival is governed by the announced default time; arriving after it forfeits the game unless the arbiter decides otherwise.

If during a game it is found that the initial position of the pieces was incorrect, the game is cancelled and a new game is played. If it is found that the chessboard was placed contrary to Article 2.1 (white corner on the right), the game continues but the position reached is transferred to a correctly placed board. If a game has begun with colours reversed, it continues unless the arbiter rules otherwise.

An illegal move is completed once the player has pressed the clock. Upon a claim, the position before the irregularity is reinstated (if it cannot be reconstructed, the game continues from the last identifiable position). For the first completed illegal move by a player in standard play, the arbiter gives the opponent two extra minutes; for the second completed illegal move by the same player, the arbiter declares the game lost by that player — unless the opponent's resulting position has no legal mating sequence, in which case the game is drawn.

If a player displaces one or more pieces, they shall re-establish the correct position on their own time. If necessary, either player may stop the clocks and ask for the arbiter's assistance. The arbiter may penalise the player who displaced the pieces. Any move played from an unlawfully altered position is handled under the illegal-move provisions of Article 7.2.

In the course of play each player is required to record their own and the opponent's moves move after move, as clearly and legibly as possible, in the algebraic notation, on the scoresheet prescribed for the competition. A player may respond to the opponent's move before recording it. The scoresheet is used to verify claims (threefold repetition, fifty-move rule) and to settle disputes.

Players may record moves either on a paper scoresheet or by entering their moves on a FIDE-certified 'electronic scoresheet' (Article 8.1.1.2), introduced into the Laws in this 2023 edition. A player must not write down moves in advance unless making a draw claim, or when sealing a move at adjournment.

If a player has less than five minutes left on the clock at some stage and does not have additional time of 30 seconds or more added with each move, then for the remainder of that period the player is not obliged to keep score (no need to meet the requirements of Article 8.1). Immediately after a flag has fallen, the player must update the scoresheet completely before moving a piece, if required by the arbiter.

A player may offer a draw only after making a move on the board and before pressing the clock; the offer is valid until the opponent accepts it, rejects it orally, or rejects it by touching a piece with the intention of moving or capturing it, or until the game ends another way. The offer is recorded by both players on the scoresheet with the symbol '='. Unreasonable or repeated draw offers that distract or annoy the opponent are forbidden and may be penalised by the arbiter.

The game is drawn upon a correct claim by the player having the move when the same position has appeared at least three times (not necessarily by repetition of moves). Positions are the same if the same player has the move, pieces of the same kind and colour occupy the same squares, and the possible moves of all the pieces (including castling and en passant rights) are the same. The player claims by writing the move on the scoresheet and declaring the intention before making it, or by claiming after a position that has just appeared for the third time.

The game is drawn upon a correct claim by the player having the move if the last 50 consecutive moves by each player have been completed without the movement of any pawn and without any capture. As with threefold repetition, the claim is made by writing the intended move on the scoresheet and declaring the intention before making it.

The game is drawn automatically, without any claim, when: (a) the same position appears for the fifth time (fivefold repetition); or (b) 75 consecutive moves by each player have been completed without the movement of any pawn and without any capture — unless the last move was checkmate, in which case the game is won. In both cases the arbiter shall declare the draw.

The game is immediately drawn (dead position) when a position arises in which neither player can checkmate the opponent's king with any series of legal moves. Typical cases include king versus king, king and bishop versus king, king and knight versus king, and king and bishop versus king and bishop of the same coloured squares.

Players shall take no action that brings the game of chess into disrepute. It is forbidden to distract or annoy the opponent in any manner whatsoever, including unreasonable claims, unreasonable or repeated draw offers, or the introduction of a source of noise into the playing area. Players may not use any notes, sources of information or advice, or analyse any game on another chessboard, during play.

During play players are forbidden to have any electronic device not specifically approved by the arbiter in the playing venue. The competition regulations may specify the penalty; if it is established that a player brought such a device into the playing venue, the player shall lose the game while the opponent wins, unless the regulations specify a different, less-severe penalty. The arbiter may require the player to allow inspection of clothing, bags and other items.

A player may claim a result (draw, win on time, illegal move) only when it is their turn and through the correct procedure; an incorrect claim (for example a wrongly claimed threefold repetition or fifty-move draw) may be penalised — typically by adding two minutes to the opponent's remaining time, and the game continues. A player who resigns does so by a clear declaration or by stopping the clock and informing the arbiter; an ambiguous gesture such as stopping the clocks is not in itself a resignation.

The arbiter shall see that the Laws of Chess are strictly observed and shall act in the best interest of the competition. The arbiter shall observe the games, especially when players are short of time, enforce decisions, and impose penalties where appropriate. The arbiter should restrict intervention to a necessary minimum and should not signal the number of completed moves, nor draw attention to a fallen flag or unrecorded move, except where the regulations require it.

The options available to the arbiter, in increasing severity, are: (a) a warning; (b) increasing the remaining time of the opponent; (c) reducing the remaining time of the offending player; (d) increasing the points scored in the game by the opponent to the maximum available; (e) reducing the points scored by the offending player; (f) declaring the game lost by the offending player; (g) a fine; (h) exclusion from one or more rounds; (i) expulsion from the competition.

Rapid and blitz games are played according to the FIDE Laws of Chess, except where overridden by the Appendix A (Rapid) and Appendix B (Blitz) rules. Where the games are played under adequate arbiter supervision (for example one arbiter per game, or per a small number of games), the Competitive Rules of Play apply in full, including the illegal-move procedure of Article 7.2.

Under adequate supervision the illegal-move procedure of Article 7.2 applies, but in rapid play the time penalty for the first completed illegal move is one minute added to the opponent (reduced from two minutes — the headline change in the 2023 Laws), and the second completed illegal move by the same player loses the game. Without adequate supervision, the opponent may claim a win for an illegal move provided they have not yet made their own next move and the position can be established. A flag-fall must still be claimed by a player; the arbiter does not call it.

A quickplay finish is the phase of a game in which all remaining moves must be completed in a finite time. In rapid and blitz, players are not required to record the moves. If both flags have fallen and it is impossible to establish which fell first, in blitz the game is drawn (in standard/rapid the arbiter is generally present to observe). A player who completes the move that produces a clearly winning result before their own flag falls is awarded that result.

Over a tournament each game contributes to a player's score: 1 point for a win, ½ for a draw, 0 for a loss. Events are commonly run as round-robin (each plays each) or Swiss systems. Tie-breaks (e.g. Buchholz, Sonneborn-Berger, direct encounter, number of wins) are applied by the competition regulations to separate players on equal points; these are defined per event, not by the Laws of Chess themselves.

In knockout matches between two players, a fixed number of classical games is played; if tied, the match is decided by a tie-break of progressively faster games — typically a mini-match of rapid games, then blitz games, and finally a single sudden-death (Armageddon) game where White has more time but Black wins the match with a draw. Each individual game still follows the Laws of Chess for its time control.