Rules of chess
The rules of chess (also known as the laws 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 (inescapably threaten with capture) the opponent's king. A game can end in various ways besides checkmate: a player can resign, and there are several ways in which 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 place to place. Today, the standard rules are set by FIDE (Fédération Internationale des Échecs), 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.
Chess is played on a chessboard, a square board divided into a grid of 64 squares (eight-by-eight) of alternating color (similar to the board used in draughts). No matter what 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:
|Number of pieces||1||1||2||2||2||8|
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 on a square, as follows:
- The rooks are placed on the outside corners, right and left edge.
- The knights are placed immediately inside of the rooks.
- The bishops are placed immediately inside of the knights.
- The queen is placed on the central square of the same color of that of the player: white queen on the white square and black queen on the black square.
- The king takes the vacant spot next to the queen.
- The 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.
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 (e.g. a Swiss system tournament or round-robin tournament) or, in the case of non-competitive play, mutual agreement, in which case some kind of random choice is often employed. A common method is for one player to conceal a piece (usually 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.
Moves of the king
Moves of a rook
Moves of a bishop
Moves of the queen
Moves of a knight
Moves of a pawn
Except for any move of the knight and castling, pieces cannot jump over other pieces. A piece is captured (or taken) when an attacking enemy piece replaces it on its square except in the case of en passant. The captured piece is thereby permanently removed from the game. The king can be put in check but cannot be captured (see below).
- The king moves exactly one square horizontally, vertically, or diagonally. A special move with the king known as castling is allowed only once per player, per game (see below).
- 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 . (This can be thought of as moving two squares horizontally then one square vertically, or moving one square horizontally then two squares vertically—i.e. in an "L" pattern.) The knight is not blocked by other pieces; it jumps to the new location.
- Pawns have the most complex rules of movement:
- A pawn moves straight forward one square, if that square is vacant. If it has not yet moved, a pawn also has the option of moving two squares straight forward, provided both squares are vacant. Pawns cannot move backwards.
- A pawn, unlike other pieces, captures differently from how it moves. A pawn can capture an enemy piece on either of the two squares diagonally in front of the pawn. It cannot move to those squares when vacant except when capturing en passant.
- The pawn is also involved in the two special moves en passant and promotion.
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. It is not allowed to move both king and rook in the same time, because "Each move must be played with one hand only." 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 (though the rook is permitted to be under attack and to pass over an attacked square);
- The castling must be or as shown in the diagram.
An unmoved king and an unmoved rook of the same color on the same rank are said to have castling rights.
When a pawn advances two squares from its original square and ends the turn adjacent to a pawn of the opponent's on the same , it may be captured en passant by that pawn of the opponent's, as if it had moved only one square forward. This capture is only legal on the opponent's next move immediately following the first pawn's advance. The diagrams on the right 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 while the white pawn on a4 is removed from the board.
If a player advances a pawn to its eighth rank, the pawn is then promoted (converted) to a queen, rook, bishop, or knight of the same color at the choice of the player (a queen is usually chosen). 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 their pawns are promoted. If the desired piece is not available, the player must call the to provide the piece.
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 (it is pinned against its own king) 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:
- Move the king to a square where it is not in check.
- Capture the checking piece (possibly with the king).
- Block the check by placing a piece between the king and the opponent's threatening piece.
If it is not possible to get out of check, the king is checkmated and the game is over (see the next section).
In informal games, it is customary to announce "check" when making a move that puts the opponent's king in check. However, in formal competitions, check is rarely announced.
End of the game
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 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.
Either player may resign at any time, conceding the game to the opponent. A player may resign by saying it verbally or by indicating it on the in any of three ways: (1) by writing "resigns", (2) by circling the result of the game, or (3) by writing "1–0" if Black resigns or "0–1" if White resigns. 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.
Illegal move in Blitz
In Blitz chess, if a player completes an illegal move, the player's opponent may claim a win before making a move (if the opponent has enough material to win). One way to claim this win is to take a King left in check by the opponent. Once the illegal move has been answered, the move stands.
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.
- The player having the move claims a draw by correctly declaring that one of the following conditions exists, or by correctly declaring an intention to make a move which will bring about one of these conditions:
- The same board position has occurred three times with the same player to move and all pieces having the same rights to move, including the right to castle or capture en passant (see threefold repetition rule).
- There has been no or pawn move in the last fifty moves by each player, if the last move was not a checkmate (see fifty-move rule).
- The arbiter intervenes to declare a draw, without a draw request necessary:
At one time, if a player was able to check the opposing king continually (perpetual check) and the player indicated their intention to do so, the game was drawn. This rule is no longer in effect; however, players will usually agree to a draw in such a situation, since either the rule on threefold repetition or the fifty-move rule will eventually be applicable.
A dead position is defined as a position where neither player can checkmate their opponent's king by any sequence of legal moves.
- Any positions with only the following pieces are dead positions, and are known as draws by :
- king against king;
- king against king and bishop;
- king against king and knight;
- king and bishop against king and bishop, with both bishops on squares of the same color (see King and two bishops).
- However, insufficient material is not the only condition for a dead position. There are positions in which checkmate is impossible but the pieces on the board would be sufficient to mate if arranged otherwise. This usually occurs in blocked king and pawn endings where it is impossible for either king to capture the pawns. See the diagram "Example of a dead position".
A game played under time control will end as a loss for a player who uses up all of the time allotted on the player's clock, which is called , unless the opponent has no possibility of effecting checkmate (see Timing). There are different types of time control. A player may have a fixed amount of time for the entire game, or may have to make a certain number of moves within a specified time. Also, a small increment of time may be added for each move made.
The following rules are the rules used for "" (OTB) games. They are defined by the FIDE Laws of Chess. The FIDE Laws of Chess define the rules for Standard chess, Rapid chess, Blitz chess and guidelines for Chess960. For Standard chess, the players must record the moves, which is optional in Rapid chess and Blitz Chess. Some rules are specifically adapted for disabled players. As the rules cover OTB play, they cannot be directly applied to computer chess or online chess, played on a computer device. The rules for correspondence chess are defined by the ICCF.
Moving the pieces
The movement of pieces is to be done with one hand. Once the hand is taken off a piece after moving it, the move cannot be retracted unless the . As for the touch-move rule, an arbiter who observes a violation of this rule must intervene immediately. A player must claim a violation of the rule immediately before making a move, or lose the right to claim.
When castling, a player should first move the king with one hand and then move the rook with the same hand.
In the case of a promotion, if a player releases the pawn on the eighth rank, the player must promote the pawn. After the pawn has moved, the player may touch any piece not on the board and the promotion is not finalized until the new piece is released on the promotion square.
In serious play, if a player having the move touches a piece as if having the intention of moving it, then the player must move it if it can be legally moved. So long as the hand has not left the piece on a new square, any legal move can be made with the piece. If a player touches one of the opponent's pieces then that piece must be if there is a legal move that does so. If none of the touched pieces can be moved or captured, there is no penalty. An arbiter who observes a violation of this rule must intervene immediately. A player must claim a violation of the rule immediately before making a move, or lose the right to claim.
When castling, the king must be the first piece touched. If the player touches the king and a rook, the player must castle with that rook if it is legal to do so. If the player completes a two-square king move without touching a rook, the player must move the correct rook accordingly if castling in that direction is legal. If a player starts to castle illegally, another legal king move must be made if possible, including castling with the other rook.
If a player moves a pawn to its eighth rank, it cannot be substituted for a different move of the pawn when the player has stopped touching it. However, the move is not complete until the promoted piece is released on that square.
If a player touches a piece to adjust its physical position within a square, he must first alert his opponent by saying J'adoube or "I adjust". Once the game has started, only the player with the move may touch the pieces on the board.
Tournament games are played under time constraints, called time controls, using a chess clock. Each player is timed separately and must make moves within the time control or forfeit the game. There are different types of time controls applied. For standard chess, different periods can be defined with different fixed times (e.g. first 40 moves in 100 minutes, next 20 moves in 50 minutes, remaining moves in 15 minutes). For rapid and blitz chess, only one period can be defined where all moves must be performed. Additionally, an increment or delay per move may be defined.
- When a player runs out of time, this event is called . A flag fall has no consequences unless stated as observed by the arbiter, in which case the arbiter must intervene, or claimed by a player.
- When no flag fall is stated, and one of the following events occur, the result of the game still holds. It is of no relevance if the player runs out of time afterwards, or has already run out of time, but this was not stated:
- If a player correctly claims flag fall, that player wins. But if the claiming player is out of time, or could not still theoretically checkmate the opponent, the game is a draw.
The United States Chess Federation (USCF) rule is different. USCF Rule 14E defines "insufficient material to win on time", that is lone king, king plus knight, king plus bishop, and king plus two knights opposed by no pawns, and there is no forced win in the final position. Hence to win on time with this material, the USCF rule requires that a win can be forced from that position, while the FIDE rule merely requires a win to be possible. (See Monika Soćko rules appeal in 2008 and Women's World Chess Championship 2008 for a famous instance of this rule.)
- With mechanical clocks only, flag fall for both players can occur. With digital clocks, the clock indicates which flag fell first, and this information is valid.
- If a flag fall is stated, and as can happen with mechanical clocks only, the flag fall happened for both players, then:
- If it can be established which player ran out of time first, the rules apply for flag fall for one player only.
- Otherwise, the result is a draw, unless this is a standard chess game which is not in the last period, here the play will be resumed.
In the last period of a standard chess game or rapid games, if played without increment, a special set of rules applies regarding the clock, referenced as "Quickplay Finishes". These rules allow a player with under two minutes time to request an increment introduced, or request a draw based on claiming no progress or no effort, to be ruled by the arbiter. These rules have been relevant when playing with mechanical clocks, which do not allow setting an increment and are today with digital clocks of second importance only, as playing with increment is recommended.
Each square of the chessboard is identified with a unique pair of a letter and a number. The vertical are labeled a through h, from White's left (i.e. the queenside) to White's right. Similarly, the horizontal are numbered from 1 to 8, starting from the one nearest White's side of the board. Each square of the board, then, is uniquely identified by its file letter and rank number. The white king, for example, starts the game on square e1. The black knight on b8 can move to a6 or c6.
In formal competition, each player is obliged to record each move as it is played in algebraic chess notation in order to settle disputes about illegal positions, overstepping time control, and making claims of draws by the fifty-move rule or repetition of position. Moves recorded in any other systems of notation cannot be used in evidence in such a dispute. Other chess notation systems include ICCF numeric notation for international correspondence chess and descriptive chess notation, formerly standard in English speaking countries. The current rule is that a move must be made on the board before it is written on paper or recorded with an electronic device.
Both players should indicate offers of a draw by writing "=" at that move on their score sheets. Notations about the time on the clocks can be made. A player with less than five minutes left to complete all the remaining moves is not required to record the moves (unless a delay of at least thirty seconds per move is being used). The score sheet must be made available to the at all times. A player may respond to an opponent's move before writing it down.
- See Adjournment § Chess.
Formerly common, adjournments are no longer standard practice in chess competition.
When an adjournment is made, the player whose move it is writes their next move on their scoresheet but does not make the move on the chessboard. This is referred to as a . Both opponents' scoresheets are then placed in the sealed-move envelope and the envelope is sealed. The names of the players, the colors, the position, the time on the clocks and other game data are recorded on the envelope; the envelope may also be signed by both players. The arbiter then keeps possession of the envelope until it is time to restart the game, at which time the arbiter opens the envelope, makes the sealed move on the board, and starts the opponent's clock.
An illegal move is a move not made according to a piece's possible defined movements  or made according to its possible movements but such that its own king is left or placed in check. Furthermore, pressing the clock without making a move or making a move with two hands is considered and penalized as an illegal move.
A player who makes an must retract that move and make a legal move. That move must be made with the same piece if possible, because the touch-move rule applies. If the illegal move was an attempt to castle, the touch-move rule applies to the king but not to the rook. If the mistake is noticed, the game should be restarted from the position in which the error occurred. The arbiter should adjust the time on the clock according to the best evidence. Some regional organizations have different rules.
A player may correct an illegal move if the player has not pressed the clock. If a player has pressed the clock, the illegal move may be stated by the arbiter intervening or by the opponent claiming the illegal move. In Standard chess, the illegal move must be claimed before the end of the game. In the most used form of Rapid chess and Blitz chess, if the arbiter does not intervene and the opponent moves, the illegal move is accepted and without penalty.
According to the FIDE Laws of Chess, the first stated completed illegal move results in a time penalty. The time penalty consists of giving the opponent two minutes extra time in standard and rapid chess, one minute extra time in Blitz. The second stated completed illegal move by the same player results in the loss of the game, unless the position is such that it is impossible for the opponent to win by any series of legal moves (e.g. if the opponent has a bare king) in which case the game is drawn. A move is completed when it has been made and the player has pressed the clock.
For Standard chess and the most used form of Rapid and Blitz chess there are the following rules. If it is discovered during the game that the starting position was incorrect, the game is restarted. If it is discovered during the game that the board is oriented incorrectly, the game is continued with the pieces transferred to a correctly oriented board. If the game starts with colours reversed, the game is restarted if less than 10 moves have been made by both players, otherwise the game is continued. If the clock setting is found to be incorrect during the game, it is corrected according to best judgement. Some regional organizations have different rules.
If a player knocks over pieces, it is the same player's responsibility to restore them to their correct positions, on that player's time. If it is discovered that an illegal move has been made, or that pieces have been displaced, the game is restored to the position before the irregularity. If that position cannot be determined, the game is restored to the last known correct position.
An illegal position is a position which cannot be reached by any series of legal moves.
Players may not use any notes, outside sources of information (including computers), or advice from other people. Analysis on another board is not permitted. Scoresheets are to record objective facts about the game only, such as time on the clock or draw offers. Players may not leave the competition area without permission of the arbiter.
High standards of etiquette and ethics are expected. Players should shake hands before and after the game. Generally a player should not speak during the game, except to offer a draw, resign, or to call attention to an irregularity. An announcement of "check" is commonly made in informal games but is not recommended in officially sanctioned games. A player may not distract or annoy another player by any means, including repeatedly offering a draw.
Due to increasing concerns about the use of chess engines and outside communication, mobile phone usage is banned. The first forfeit by a high-profile player, for phone ringing during play, occurred in 2003. In 2014 FIDE extended this to ban all mobile phones from the playing area during chess competitions, under penalty of forfeiture of the game or even expulsion from the tournament. The rules allow for less rigid enforcement in minor events.
The size of the squares of the chessboard should be approximately 1.25 to 1.3 times the diameter of the base of the king, or 50 to 65 mm. Squares of approximately 57 mm (2+1⁄4 inches) normally are well-suited for pieces with the kings in the preferred size range. The darker squares are usually brown or green and the lighter squares are off-white or buff.
Pieces of the Staunton chess set design are the standard and are usually made of wood or plastic. They are often black and white; other colors may be used (like a dark wood or even red for the dark pieces) but they would still be called the "white" and "black" pieces (see White and Black in chess). The height of the king should be 85 to 105 millimetres (3.35–4.13 inches). A height of approximately 95 to 102 mm (3+3⁄4–4 inches) is preferred by most players. The diameter of the king should be 40 to 50% of its height. The size of the other pieces should be in proportion to the king. The pieces should be well balanced.
In games subject to time control, a chess clock is used, consisting of two adjacent clocks and buttons to stop one clock while starting the other, such that the two component clocks never run simultaneously. The clock can be analog or digital though a digital clock is highly preferred under both USCF and FIDE rulesets. This is since most tournaments now include either an increment (extra time being added prior or after the move) or delay (a countdown to when a clock starts again) to their time controls. Before the start of the game, either the arbiter or whoever is playing Black decides where the chess clock is placed.
The rules of chess have evolved much over the centuries from the early chess-like games played in India in the 6th century. For much of that time the rules have varied from area to area. The modern rules first took form in southern Europe during the 13th century, giving more mobility to pieces that previously had more restricted movement (such as the queen and bishop). Such modified rules entered into an accepted form during the late 15th century or early 16th century. The basic moves of the king, rook, and knight are unchanged. A pawn originally did not have the option of moving two squares on its first move, and promoted only to a queen upon reaching the eighth rank. The queen was originally the fers or farzin, which could move one square diagonally in any direction. In European chess it became able to leap two squares diagonally, forwards, backwards, or to left or right on its first move; some areas also gave this right to a newly promoted pawn. In the Persian and Arabic game the bishop was a pīl (Persian) or fīl (Arabic) (meaning "elephant") which moved two squares diagonally with jump. In the Middle Ages the pawn could only be promoted to the equivalent of a queen (which at that time was a weak piece) if it reached its eighth rank. During the 12th century, the squares on the board sometimes alternated colors, and this became the standard in the 13th century; whence the word "chequered"/"checkered".
Between 1200 and 1600 several laws emerged that drastically altered the game. Checkmate became a requirement to win; a player could not win by capturing all of the opponent's pieces. Stalemate was added, although the outcome has changed several times (see History of the stalemate rule). Pawns gained the option of moving two squares on their first move, and the en passant rule was a natural consequence of that new option. The king and rook acquired the right to castle (see Castling#History for different versions of the rule).
Between 1475 and 1500, the queen and the bishop also acquired their current moves, which made them much stronger pieces. When all of these changes were accepted, the game was in essentially its modern form.
The rules for promotion have changed several times. As stated above, originally the pawn could only be promoted to the queen, which at that time was a weak piece. When the queen acquired its current move and became the most powerful piece, the pawn could then be promoted to a queen or a rook, bishop, or knight. In the 18th century rules allowed only the promotion to a piece already captured, e.g. the rules published in 1749 by François-André Danican Philidor. In the 19th century, this restriction was lifted, which allowed for a player to have more than one queen, e.g. the 1828 rules by Jacob Sarratt.
Two new rules concerning draws were introduced, each of which have changed through the years:
- The threefold repetition rule was added, although at some times up to six repetitions have been required, and the exact conditions have been specified more clearly (see Threefold repetition#History).
- The fifty-move rule was also added. At various times, the number of moves required was different, such as 24, 60, 70, or 75. For several years in the 20th century, the standard fifty moves was extended to one hundred moves for a few specific endgames (see Fifty-move rule's history).
Another group of new laws included (1) the touch-move rule and the accompanying "j'adoube/adjust" rule; (2) that White moves first (in 1889); (3) the orientation of the board; (4) the procedure if an illegal move was made; (5) the procedure if the king had been left in check for some moves; and (6) issues regarding the behavior of players and spectators. The Staunton chess set was introduced in 1849 and it became the standard style of pieces. The size of pieces and squares of the board was standardized.
Until the middle of the 19th century, chess games were played without any time limit. In an 1834 match between Alexander McDonnell and Louis-Charles Mahé de La Bourdonnais, McDonnell took an inordinate amount of time to move, sometimes up to 1½ hours. In 1836 Pierre Charles Fournier de Saint-Amant suggested a time limit, but no action was taken. At the 1851 London tournament, Staunton blamed his loss in his match against Elijah Williams on Williams' slow play; one game was adjourned for the day after only 29 moves. The next year a match between Daniel Harrwitz and Johann Löwenthal used a limit of 20 minutes per move. The first use of a modern-style time limit was in an 1861 match between Adolph Anderssen and Ignác Kolisch.
The first known publication of chess rules was in a book by Luis Ramírez de Lucena about 1497, shortly after the movement of the queen, bishop, and pawn were changed to their modern form. Ruy López de Segura gave rules of chess in his 1561 book Libro de la invencion liberal y arte del juego del axedrez. In the 16th and 17th centuries, there were local differences concerning rules such as castling, promotion, stalemate, and en passant. Some of these differences persisted until the 19th century; for example, differences in castling rules persisted in Italy until the late 19th century.
As chess clubs arose and tournaments became common, there was a need to formalize the rules. In 1749 Philidor (1726–1795) wrote a set of rules that were widely used, as well as rules by later writers such as the 1828 rules by Jacob Sarratt (1772–1819) and rules by George Walker (1803–1879). In the 19th century, many major clubs published their own rules, including The Hague in 1803, London in 1807, Paris in 1836, and St. Petersburg in 1854. In 1851 Howard Staunton (1810–1874) called for a "Constituent Assembly for Remodeling the Laws of Chess" and proposals by Tassilo von Heydebrand und der Lasa (1818–1889) were published in 1854. Staunton had published rules in Chess Player's Handbook in 1847, and his new proposals were published in 1860 in Chess Praxis; they were generally accepted in English-speaking countries. German-speaking countries usually used the writings of chess authority Johann Berger (1845–1933) or Handbuch des Schachspiels by Paul Rudolf von Bilguer (1815–1840), first published in 1843.
In 1924, Fédération Internationale des Échecs (FIDE) was formed and in 1928 it took up the task of standardizing the rules. At first FIDE tried to establish a universal set of rules, but translations to various languages differed slightly. Although FIDE rules were used for international competition under their control, some countries continued to use their own rules internally. In 1952, FIDE created the Permanent Commission for the Rules of Chess (also known as the Rules Commission) and published a new edition of the rules. The third official edition of the laws was published in 1966. The first three editions of the rules were published in French, with that as the official version. In 1974 FIDE published the English version of the rules (which was based on an authorized 1955 translation). With that edition, English became the official language of the rules. Another edition was published in 1979. Throughout this time, ambiguities in the laws were handled by frequent interpretations that the Rules Commission published as supplements and amendments. In 1982, the Rules Commission rewrote the laws to incorporate the interpretations and amendments. In 1984, FIDE abandoned the idea of a universal set of laws, although FIDE rules are the standard for high-level play. With the 1984 edition, FIDE implemented a four-year moratorium between changes to the rules. Other editions were issued in 1988 and 1992.
The rules of national FIDE affiliates (such as the United States Chess Federation, or USCF) are based on the FIDE rules, with slight variations. Some other differences are noted above. Kenneth Harkness published popular rulebooks in the United States starting in 1956, and the USCF continues to publish rulebooks for use in tournaments it sanctions.
In 2008, FIDE added the variant Chess960 to the appendix of the "Laws of Chess". Chess960 uses a random initial set-up of main pieces, with the conditions that the king is placed somewhere between the two rooks, and bishops on opposite-color squares. The castling rules are extended to cover all these positions.
From time to time, rules have been introduced at certain tournaments to discourage players from agreeing to short draws. One such case was the "no drawing or resigning during the first 30 moves" rule used at the 2009 London Chess Classic.
- (FIDE 2008)
- (Schiller 2003:16–17)
- When promoting a pawn, a piece previously captured and removed from the board is often used as the "new" promoted piece. The new piece is nevertheless regarded as distinct from the original captured piece; the physical piece is used simply for convenience. Moreover, the player's choice for promotion is not restricted to pieces that were previously captured.
- (Schiller 2003:17–19)
- "FIDE Laws of Chess taking effect from 1 January 2018". FIDE. Retrieved 12 July 2020.
- Article 4.1 in FIDE Laws of Chess
- Article 3.8.2 in FIDE Laws of Chess
- Article 6.11.2 in FIDE Laws of Chess
- "ARBITERS'S MANUAL 2020" (PDF). FIDE Arbiter's Commission. p. 13. Retrieved 12 July 2020.
When a player places an inverted (upside-down) Rook on the promotion square and continues the game, the piece is considered as a Rook, even if he names it as a "Queen" or any other piece.
- (Harkness 1967)
- (Just 2014)
- (Polgar & Truong 2005:32, 103)
- (Burgess 2009:550)
- (Just 2014)
- (Harkness 1967)
- (Schiller 2003:20–21)
- Article 1.4.1 in FIDE Laws of Chess
- (Schiller 2003:21)
- (Just 2014)
- USCF Chess Rule Book, chapter 11: Blitz Chess, p. 120, art. 7d: "[A game is won by the player:] 7d.) Who, after an illegal move is completed by the opponent, takes the king (if the king is in check) or claims the win and stops the clock, before the player determines a move and provided the player has sufficient mating material as defined in rule 7c. A player who moves his king adjacent to the opponent’s king and then attempts to claim a win under this rule based on the opponent’s failure to notice the check shall lose the game."
- (Harkness 1967)
- Articles 9.2.1 and 9.3 in FIDE Laws of Chess
- (Staunton 1847:21–22)
- (Reinfeld 1954:175)
- Comment to Article 1.5 in Arbiter's manual
- Article 5.2.2 "The game is drawn when a position has arisen in which neither player can checkmate the opponent's king with any series of legal moves. The game is said to end in a 'dead position'." in the FIDE Laws of Chess
- "US_Chess_Rule_Book- Online_Only_Edition_v7.1-1.2.11-7.19.19.pdf" (PDF). The United States Chess Federation. Retrieved 17 July 2020.
- Article "14D. Insufficient material to continue" in USCF Laws of Chess
- Article 8 and Appendices A and B in FIDE Laws of Chess
- Article 4.7 in FIDE Laws of Chess
- Comment to Article 4 in Arbiter's manual
- Article 4.8 in FIDE Laws of Chess
- (Schiller 2003:19–20)
- (Just 2014)
- (Schiller 2003:19–20)
- The United States Chess Federation has a variation that tournament directors can use. If a player intending to castle touches the rook first, there is no penalty. However, if castling is illegal, the touch-move rule applies to the rook. This variation does not have to be announced in pre-tournament publicity but should be announced at the start of the tournament. "Rulebook Changes" (PDF).
- Article 4.4.1 in FIDE Laws of Chess
- (Schiller 2003:20)
- J'adoube /ʒadub/, from the verb adouber which is obsolete French except in chess (meaning "to touch") and in chivalry stories (meaning "to knight"), is always understood. The national-language equivalent may be used if the opponent is known to understand it but should be avoided in international tournaments and against a foreign opponent.
- (Schiller 2003:19–20)
- Comment to Article 6.3.2 in Arbiter's Manual
- For standard chess by Article 6.8, for rapid chess by Article 6.8 if using competition rules, otherwise A.4.5, for blitz chess by Article 6.8 if using competition rules, otherwise rapid chess rules are used so by A.4.5 in FIDE Laws of Chess.
- Article 6.8 in FIDE Laws of Chess
- Article 18.104.22.168 concerning mate in FIDE Laws of Chess
- Article 22.214.171.124 concerning draw in FIDE Laws of Chess
- Article 6.9 in Fide Laws of Chess
- Comment to Article 6.4 "Where electronic clocks are used and both clocks show 0.00, the Arbiter can usually establish which flag fell first, with the help of the ‘-‘ or any other flag indication." in Arbiter's manual
- Article III.3.1 in FIDE Laws of Chess
- "Standards of Chess Equipment, venue for FIDE Tournaments, rate of play and tie-break regulations" (PDF). FIDE. Retrieved 16 July 2020.
- Article 5.4.2, "In approved clocks, when both flags fall down must be seen which flag fell first.", in "FIDE Standards of Chess Equipment, venue for FIDE Tournaments, rate of play and tie-break regulations"
- "III. Games without increment including Quickplay Finishes" under Guidelines in Fide Laws Of Chess
- Guideline III.5.2 comment "A time control with an increment is a much better way of concluding a game." in Arbiter's Manual
- In a variation of the rules, a USCF director may allow players to write their move on a paper (but not enter it electronically) before making the move. Ref: USCF rule changes as of August 2007 (requires registration) or PDF retrieved Dec 4, 2009. "Rule 15A. (Variation I) Paper scoresheet variation. The player using a paper scoresheet may first make the move, and then write it on the scoresheet, or vice versa. This variation does not need to be advertised in advance."
- Before this was the rule, Mikhail Tal and others were in the habit of writing the move before making it on the board. Unlike other players, Tal did not hide the move after he had written it – he liked to watch for the reaction of his opponent before he made the move. Sometimes he crossed out a move he had written and wrote a different move instead.
- (Timman 2005:83)
- (Schiller 2003:27)
- (Schiller 2003:25–26)
- Article 3.10.1 in FIDE Laws of Chess
- Articles 3.2 to 3.8 in FIDE Laws of Chess
- Article 3.9 in FIDE Laws of Chess
- Articles 7.5.3 and 7.5.4 in FIDE Laws of Chess
- Article 7.5.1 in FIDE Laws of Chess
- The USCF requires that only an illegal move within the last ten moves be corrected. If the illegal move was more than ten moves ago, the game continues.
- (Just 2014)
- Appendices A.4.2 and B.4 in FIDE Laws of Chess
- If the player has pressed the clock, the standard USCF rule is that two minutes are added to the opponent's clock.
- Article 7.5.5 and B.2 in FIDE Laws of Chess
- Article 7.5.5 in FIDE Laws of Chess
- Article 6.2.1 in FIDE Laws of Chess
- Articles 7.2.1, 7.2.2 and 7.3 in FIDE Laws of Chess
- Article 6.10.2 in FIDE Laws of Chess
- The USCF rules are different. If before Black's tenth move is completed it is discovered that the initial position was wrong or that the colors were reversed, the game is restarted with the correct initial position and colors. If the discovery is made after the tenth move, the game continues.
- (Just 2014)
- Articles 7.5.1 and 7.6 in FIDE Laws of Chess
- Article 3.10.3 in FIDE Laws of Chess
- (Schiller 2003:30–31)
- (Schiller 2003:30–31, 49–52)
- "I just called to say... you’re disqualified!", The Scotsman, 19 October 2003
- New FIDE anti-cheating rules, ChessBase, 17 September 2014
- The 1988 and 2006 FIDE rules specify 85–105 mm; the 2008 rules simply say "about 95 mm".
- (FIDE 1989:121)
- (Just 2014)
- The US Chess Federation allows the height of the king to be 86–114 mm (3+3⁄8–4+1⁄2 inches).
- (Hooper & Whyld 1992:41, 328) harvcol error: no target: CITEREFHooperWhyld1992 (help)
- (Ruch 2004)
- (Davidson 1949:13)
- (Davidson 1949:59–61)
- (Davidson 1949:146)
- A History of Chess
- (Davidson 1949:14–17)
- (Davidson 1949:14–17)
- (Davidson 1949:59–61)
- "Scholar's Mate issue 102".
- (Hooper & Whyld 1992:220–21, laws, history of) harvcol error: no target: CITEREFHooperWhyld1992 (help)
- Howard Staunton, The Chess Tournament – A Collection of Games Played at this Celebrated Assemblage, London 1852, p. 161
- (Sunnucks 1970:459)
- (Just 2014)
- (Sunnucks 1970:294)
- (Harkness 1967:3)
- (Hooper & Whyld 1992:220–21) harvcol error: no target: CITEREFHooperWhyld1992 (help)
- (FIDE 1989:7–8)
- (Hooper & Whyld 1992:220–21) harvcol error: no target: CITEREFHooperWhyld1992 (help)
- (FIDE 1989:5)
- (Just 2014)
- (Just 2014)
- Schiller states that the United States is the only country that does not follow the FIDE rules. Some of the differences in the US Chess Federation rules are (1) a player must have a reasonably complete to claim a time forfeit and (2) the player can choose whether or not to use a clock with a delay period for each move.
- (Schiller 2003:123–24)
- "II.3 Chess960 castling rules" under Guidelines in FIDE Laws of Chess
- pages W1 and W2 of "Weekend" supplement of the Daily Telegraph newspaper for 21 November 2009
- Burgess, Graham (2009), The Mammoth Book of Chess (3rd ed.), Running Press, ISBN 978-0-7624-3726-9
- Davidson, Henry (1949), A Short History of Chess (1981 ed.), McKay, ISBN 0-679-14550-8
- FIDE (1989), The Official Laws of Chess, Macmillan, ISBN 0-02-028540-X
- FIDE (2008), FIDE Laws of Chess, FIDE, ISBN 978-0-9594355-2-8, retrieved 2008-09-10
- Harkness, Kenneth (1967), Official Chess Handbook, McKay
- Hooper, David; Whyld, Kenneth (1996) [First pub. 1992], The Oxford Companion to Chess (2nd ed.), Oxford University Press, ISBN 0-19-280049-3
- Just, Tim (2014), U.S. Chess Federation's Official Rules of Chess (6th ed.), McKay, ISBN 978-0-8129-3559-2
- Polgar, Susan; Truong, Paul (2005), A World Champion's Guide to Chess, Random House, ISBN 978-0-8129-3653-7
- Reinfeld, Fred (1954), How To Be A Winner At Chess, Fawcett, ISBN 0-449-91206-X
- Ruch, Eric (2004), The Italian Rules, ICCF, retrieved 2008-09-10
- Schiller, Eric (2003), Official Rules of Chess (2nd ed.), Cardoza, ISBN 978-1-58042-092-1
- Staunton, Howard (1847), The Chess-Player's Handbook, London: H. G. Bohn, pp. 21–22, ISBN 0-7134-5056-8 (1985 Batsford reprint, ISBN 1-85958-005-X)
- Sunnucks, Anne (1970), The Encyclopaedia of Chess, St. Martin's Press (2nd ed.), ISBN 978-0-7091-4697-1
- Timman, Jan (2005), Curaçao 1962: The Battle of Minds that Shook the Chess World, New in Chess, ISBN 978-90-5691-139-3
- Golombek, Harry, ed. (1976), The Laws of Chess and their Interpretations, Pitman, ISBN 0-273-00119-1
- Golombek, Harry (1977), Golombek's Encyclopedia of Chess, Crown Publishing, ISBN 0-517-53146-1
- Harkness, Kenneth (1970), Official Chess Rulebook, McKay, ISBN 0-679-13028-4