Rules of chess

Therules of chess(also known as thelaws of chess) govern the play of the game ofchess.Chess is a two-playerabstract strategyboard game.Each player controls sixteenpiecesof six types on achessboard.Each type of piece moves in a distinct way. The object of the game is tocheckmatethe opponent'sking;checkmate occurs when a king is threatened with capture and has no escape. A game can end in various ways besides checkmate: a player canresign,and there are several ways a game can end in adraw.

Stauntonstyle chess pieces.Left to right:king, rook, queen, pawn, knight, bishop

While the exactorigins of chessare 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 byFIDE(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 forfast chess,correspondence chess,online chess,andChess960.

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 usingchess notation.Procedures for resolving irregularities that can occur during a game are provided as well.

Initial setup

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Starting position

Chess is played on achessboard,a square board divided into a grid of 64 squares (eight-by-eight) of alternating color (similar to the board used indraughts).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 calledranks,and vertical columns are calledfiles.

Each player controls sixteen pieces:

Piece	King	Queen	Rook	Bishop	Knight	Pawn
Number of pieces	1	1	2	2	2	8
Symbols

At the beginning of the game, the pieces are arranged as shown in the diagram: for each side oneking,onequeen,tworooks,twobishops,twoknights,and eightpawns.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

A game in a public park inKyiv,using achess clock

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 isdetrimental.Play continues until a king ischeckmated,a playerresigns,or adrawis declared, as explained below.In addition, if the game is being played under atime control,a player who exceeds thetime limitloses 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. aSwiss system tournamentorround-robin tournament) 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

Moves of the king

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Moves of a rook

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Moves of a bishop

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Moves of the queen

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Moves of a knight

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Moves of a pawn

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The pawns can move to the squares in front of them (white dots). The pawn on c6 can also take either black rook.

Each type of chess piece has its own method of movement. A piece moves to a vacant square except whencapturingan opponent's piece.

Except for any move of the knight andcastling,pieces cannot jump over other pieces. A piece iscaptured(ortaken) 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 incheckbut cannot be captured (see below).

• Thekingmoves exactly one square horizontally, vertically, or diagonally. A special move with the king known ascastlingis allowed only once per player, per game (see below).
• Arookmoves any number of vacant squares horizontally or vertically. It also is moved when castling.
• Abishopmoves any number of vacant squares diagonally. (Thus a bishop can move to only light or dark squares, not both.)
• Thequeenmoves any number of vacant squares horizontally, vertically, or diagonally.
• Aknightmoves to one of the nearest squares not on the samerank,file,ordiagonal.(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.
• Pawnshave 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 movingtwosquares 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 capturingen passant.

The pawn is also involved in the two special movesen passantandpromotion.

Castling

Main article:Castling

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Position of pieces before castling

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Positions of the king and rook after kingside (White) and queenside (Black) 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 (though the rook is permitted to be under attack and to pass over an attacked square);
• 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 havecastling rights.

En passant

Main article:En passant

en passant

When a pawn advances two squares on its initial move and ends the turn adjacent to an enemy pawn on the samerank,it may be captureden passantby 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 iten passant,moving from b4 to a3, and the white pawn on a4 is removed from the board.

Promotion

Main article:Promotion (chess)

If a player advances a pawn to its eighth rank, the pawn is thenpromoted(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 previouslycapturedpieces. 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

Main article:Check (chess)

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Black's king is in check. It can get out of check by moving to an unattacked square. Black can also parry the check by moving the bishop to e5 or the knight to f4 to block the check, or by capturing the white bishop with the knight.

A king isin checkwhen 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 ispinnedagainst 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:

• Movethe king to a square where it is not in check.
• Capturethe checking piece.
• Interposea piece between the king and the opponent's threatening piece (blockthe check).

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

Main article:Checkmate

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White is checkmated; Black wins.

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 becheckmated,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 mayresignat 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

Main article:Draw (chess)

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Black to move is in stalemate, since Black's king has no legal move, and is not in check. The game is drawn.

The game ends in adrawif any of these conditions occur:

• The player to move is not in check and has no legal move. This situation is called astalemate.An example of such a position is shown in the adjacent diagram.
• The game reaches adead position.
• Both playersagree to a drawafter one of the players makes such an offer.

In addition, in the FIDE rules, if a player has run out of time (see below), 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 playallow 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 (this is thefifty-move rule);
• The same position has appeared three times (or has appeared twice and the player claiming the draw can force the third appearance); this is thethreefold repetitionrule.

These rules help prevent games from being extended indefinitely in tournaments.

There is no longer a rule specifically definingperpetual checkas 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

Example of a dead position

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White has just played h5; neither side can open up the position.

Adead positionis 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.

USCFrules, 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.

Touch-move rule

Main article:Touch-move rule

Thetouch-move ruleis a fundamental principle in chess, ensuring that players commit to moves deliberated mentally, without physically experimenting on the board. According to this rule, a player who touches a piece with the intention of moving it must then move it if legally possible. This rule also applies to capturing: a player who touches an opponent's piece must capture it if a legal capture is available. Special considerations apply for castling and pawn promotion, reflecting their unique nature in the game.

A player who touches a piece to adjust its physical position within a square must first alert the opponent by sayingJ'adoubeor "I adjust".Once the game has started, only the player with the move may touch the pieces on the board.

Competitive rules of play

The following rules are applicable to games in organized tournaments and matches, sanctioned by FIDE. They mention timing (chess clocks), arbiters (or, in USCF play, directors), keeping score, and adjournment. The FIDE Laws of Chess define the rules for standard chess,rapid chess,blitz chess,and guidelines forChess960.For standard chess, the players must record the moves, which is optional in rapid chess and blitz Chess.Some rules are specifically adapted for blind and visually impaired players.

These rules are used forover-the-board(OTB) games. The rules forcorrespondence chessare defined by theICCF.Rules for computer chess and for online chess played on a computer device are published by other organizers and governing bodies.

Moving the pieces

Although the touch-move rule is generally observed even in non-organized, non-sanctioned play, the interpretation of that rule to special situations such as capturing, castling, and promotion is not obvious; thus it is elaborated further in FIDE rules.

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 themove is illegal.As for thetouch-move rule,an arbiter who observes a violation of this rule must intervene immediately.

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 apromotion,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.Although it is a common practice in informal play, under FIDE rules an upturned rook may not be used to represent a promoted queen; such a move would be treated as a legal rook promotion. If the correct piece is not immediately available, the player may stop the clocks and call the arbiter.

Timing

Digital chess clock

Tournament games are played under time constraints, calledtime controls,using achess 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, anincrement or delayper move may be defined.

• When a player runs out of time, this event is calledflag-fall.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 delivers a checkmate, the game is over and that player wins.
  • If a move results in astalemate,dead position,fivefold repetitionor theseventy-five-moverule applies, the game is over and the game is drawn.
• 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.

TheUnited 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.(SeeMonika Soćko rules appeal in 2008andWomen's World Chess Championship 2008for 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.

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.

Recording moves

Main articles:Chess notationandAlgebraic chess notation

Naming the squares inalgebraic notation

A score sheet from a game byJosé Raúl Capablanca,indescriptive notation

Each square of thechessboardis identified with a unique pair of a letter and a number. The verticalfilesare labeledathroughh,from White's left (i.e. thequeenside) to White's right. Similarly, the horizontalranksare numbered from1to8,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 squaree1.The black knight onb8can move toa6orc6.

In formal competition, each player is obliged to record each move as it is played inalgebraic chess notationin 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 includeICCF numeric notationfor internationalcorrespondence chessanddescriptive 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 thearbiterat all times. A player may respond to an opponent's move before writing it down.

Adjournment

SeeAdjournment (games) § 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 asealed move.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.

Irregularities

Illegal move

An illegal moveis a move not made according to a piece's possible defined movementsor 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 anillegal movemust 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. In standard chess, if a move is found during the game, the position immediately before the irregularity is reinstated.In the most used form of rapid chess and blitz chess if the move is found before the opponent moves, the position immediately before the irregularity is also reinstated.

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 chess,or one minute extra time in rapid or 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 abare king) in which case the game is drawn.A move is completed when it has been made and the player has pressed the clock.

Under USCF rules, if a player completes an illegal move in blitz chess, 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.

Incorrect setup

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 colors 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.

Piece displacement

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.

Illegal position

An illegal position is a position which cannot be reached by any series of legal moves.

Conduct

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 ofchess enginesand outside communication,mobile phoneusage 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.

Equipment

Main articles:Chess piece,Chessboard,Staunton chess set,andChess clock

Original Staunton chess pieces, introduced in 1849.Left to right:pawn,rook,knight,bishop,queen,andking.

Pieces of theStaunton chess setdesign 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 (seeWhite and Black in chess).The height of the king should be about 95 mm, within 10 percent.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.

Pieces at the start of a game and an analogchess clock

The size of the squares of thechessboardshould 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+1⁄4inches) normally are well-suited for pieces with the kings in the preferred size range; four pawns should fit on a square.Squares may be the natural color of the wood, or other combinations of dark and light colors.

In games subject totime control,achess clockis 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 beanalogordigitalthough a digital clock is preferred under both USCF and FIDE rulesets. This is because most tournaments now include either anincrement(extra time being added prior or after the move) ordelay(a countdown to when a clock starts again) to their time controls.Before the start of the game, in FIDE competitions the arbiter decides where the chess clock is placed;in USCF competitions the director may decide, or the director may leave it to the players, in which case the player with the black pieces will decide.

History

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 centuryor 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 thefersorfarzin,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 apīl(Persian) orfīl(Arabic) (meaning "elephant" ) which moved two squares diagonally with jump.In the Middle Ages the pawn could only bepromotedto 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".

Philidor

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.Stalematewas added, although the outcome has changed several times (seeHistory of the stalemate rule). Pawns gained the option of moving two squares on their first move, and theen passantrule was a natural consequence of that new option. The king and rook acquired the right tocastle(seeCastling § Historyfor 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 byFrançois-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 byJacob Sarratt.

Two new rules concerning draws were introduced, each of which has changed through the years:

• Thethreefold repetitionrule was added, although at some times up to six repetitions have been required, and the exact conditions have been specified more clearly (seeThreefold repetition § History of the rule).
• Thefifty-move rulewas 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 specificendgames(seeFifty-move rule's history).

Another group of new laws included (1) thetouch-move ruleand 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. TheStaunton chess setwas 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 betweenAlexander McDonnellandLouis-Charles Mahé de La Bourdonnais,McDonnell took an inordinate amount of time to move, sometimes up to 1½ hours. In 1836Pierre Charles Fournier de Saint-Amantsuggested a time limit, but no action was taken. At the1851 London tournament,Staunton blamed his loss in his match againstElijah Williamson Williams' slow play; one game was adjourned for the day after only 29 moves.The next year a match betweenDaniel HarrwitzandJohann Löwenthalused a limit of 20 minutes per move. The first use of a modern-style time limit was in an 1861 match betweenAdolph AnderssenandIgnác Kolisch.

Codification

FIDE rulebook, 1989

Official Chess Rulebook,by Harkness (1970 edition)

The first known publication of chess rules was in a book byLuis Ramírez de Lucenaabout 1497, shortly after the movement of the queen, bishop, and pawn were changed to their modern form.Ruy López de Seguragave rules of chess in his 1561 bookLibro 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, anden 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 1749Philidor(1726–1795) wrote a set of rules that were widely used, as well as rules by later writers such as the 1828 rules byJacob Sarratt(1772–1819) and rules byGeorge 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 1851Howard Staunton(1810–1874) called for a "Constituent Assembly for Remodeling the Laws of Chess" and proposals byTassilo von Heydebrand und der Lasa(1818–1889) were published in 1854. Staunton had published rules inChess Player's Handbookin 1847, and his new proposals were published in 1860 inChess Praxis;they were generally accepted in English-speaking countries. German-speaking countries usually used the writings of chess authorityJohann Berger(1845–1933) orHandbuch des SchachspielsbyPaul 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 theUnited States Chess Federation,or USCF) are based on the FIDE rules, with slight variations.Some other differences are noted above.Kenneth Harknesspublished 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 variantChess960to 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.

In the 21st century, rules about such things asmobile phonesand unauthorized use ofchess engineswere introduced.

Customizations in tournament play

Under FIDE's Laws of Chess, tournament organizers have the option to parameterize some rules to fit their events. This flexibility covers time controls for standard, rapid, and blitz chess,and setting the 'default time' - the period before a player forfeits for being late, which is zero unless otherwise specified.Additionally, measures can be introduced to discourage players fromagreeing to short draws.One such case was the "no drawing or resigning during the first 30 moves" rule used at the2009 London Chess Classic.

See also

• Algebraic chess notation
• Cheating in chess
• Chess
• Chessboard
• Chess clock
• Chess glossary
• Chess piece
• Chess tournament

Specific rules

• Adjournment (games)(rare now)
• Castling
• Check
• Checkmate
• Draw
• Draw by agreement
• En passant
• Fifty-move rule
• Perpetual check(former rule)
• Promotion
• Stalemate
• Threefold repetition
• Time control
• Touch-move rule

References

Bibliography

• Burgess, Graham(2009),The Mammoth Book of Chess(3rd ed.), Running Press,ISBN978-0-7624-3726-9
• Davidson, Henry (1949),A Short History of Chess(1981 ed.), McKay,ISBN0-679-14550-8
• FIDE(1989),The Official Laws of Chess,Macmillan,ISBN0-02-028540-X
• FIDE(2023)."FIDE Laws of Chess taking effect from 1 January 2023".FIDE.Retrieved2024-02-07.
• FIDE Arbiters' Commission (2022)."Arbiters' Manual 2022"(PDF).FIDE Arbiters' Commission.Retrieved2024-02-07.
• FIDE(2022)."Standards of Chess Equipment".FIDE.Retrieved2024-02-20.
• 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,ISBN0-19-280049-3
• Just, Tim (2014),U.S. Chess Federation's Official Rules of Chess(6th ed.), McKay,ISBN978-0-8129-3559-2
• Just, Tim (2019),U.S. Chess Federation's Official Rules of Chess(PDF)(7th ed.), (independently published),ISBN978-1-7977-1690-9
• Pandolfini, Bruce (1992),Pandolfini's Chess Complete,Fireside,ISBN0-671-70186-X
• Polgar, Susan;Truong, Paul(2005),A World Champion's Guide to Chess,Random House,ISBN978-0-8129-3653-7
• Reinfeld, Fred(1954),How To Be A Winner At Chess,Fawcett,ISBN0-449-91206-X
• Ruch, Eric (2004),The Italian Rules,ICCF,retrieved2008-09-10
• Schiller, Eric(2003),Official Rules of Chess(2nd ed.), Cardoza,ISBN978-1-58042-092-1
• Staunton, Howard(1847),The Chess-Player's Handbook,London: H. G. Bohn, pp.21–22,ISBN0-7134-5056-8(1985 Batsford reprint,ISBN1-85958-005-X)
• Sunnucks, Anne(1970),The Encyclopaedia of Chess,St. Martin's Press (2nd ed.),ISBN978-0-7091-4697-1
• Timman, Jan(2005),Curaçao 1962: The Battle of Minds that Shook the Chess World,New in Chess,ISBN978-90-5691-139-3

Further reading

• Golombek, Harry,ed. (1976),The Laws of Chess and their Interpretations,Pitman,ISBN0-273-00119-1
• Golombek, Harry(1977),Golombek's Encyclopedia of Chess,Crown Publishing,ISBN0-517-53146-1
• Harkness, Kenneth (1970),Official Chess Rulebook,McKay,ISBN0-679-13028-4

External links

• FIDE Laws of Chess
• FIDE Standards of Chess Equipment
• USCF Learn to play chess