Algebraic notation (chess)


Algebraic notation is a method for recording and describing the moves in a game of chess. It is based on a system of coordinates to uniquely identify each square on the chessboard. It is now standard among all chess organizations and most books, magazines, and newspapers. In English-speaking countries, the parallel method of descriptive notation was generally used in chess publications until about 1980. Some older players still use descriptive notation, but it is no longer recognized by FIDE.
Algebraic notation exists in various forms and languages and is based on a system developed by Philipp Stamma. Stamma used the modern names of the squares, but he used p for pawn moves and the original of a piece instead of the initial letter of the piece name. This article describes standard algebraic notation required by FIDE.

Naming the squares

Each square of the chessboard is identified by a unique coordinate pair—a letter and a number. The vertical columns of squares, called ', are labeled a through h from White's left to right. The horizontal rows of squares, called ', are numbered 1 to 8 starting from White's side of the board. Thus each square has a unique identification of file letter followed by rank number.

Naming the pieces

Each piece type is identified by an uppercase letter. English-speaking players use the letters K for king, Q for queen, R for rook, B for bishop, and N for knight. S was also used for the knight in the early days of algebraic notation and is still used in some chess problems.
Players who speak other languages may employ different letters; for example, French-speaking players use F for bishop. In chess literature, especially that intended for an international audience, the language-specific letters are often replaced by universal icons for the pieces, for example, Nf3 is represented as ♘f3. This style is known as figurine algebraic notation.
Pawns are not identified by uppercase letters, but rather by the absence of one. Distinguishing between pawns is not necessary for recording moves, since only one pawn can move to a given square.

Notation for moves

Each move of a piece is indicated by the piece's uppercase letter, plus the coordinate of the destination square. For example, Be5, Nf3. For pawn moves, a letter indicating pawn is not used, only the destination square is given. For example, c5.

Captures

When a piece makes a, an "x" is inserted immediately before the destination square. For example, Bxe5. When a pawn makes a capture, the file from which the pawn departed is used to identify the pawn. For example, exd5. A colon is sometimes used instead of "x", either in the same place the "x" would go or at the end, but using it is not allowed by FIDE rules.
En passant captures are indicated by specifying the capturing pawn's file of departure, the "x", the destination square, and the suffix "e.p." indicating the capture was en passant. For example, exd6e.p.
Some texts, such as the Encyclopaedia of Chess Openings, omit any indication that a capture has been made. When it is unambiguous to do so, a pawn capture is sometimes described by specifying only the files involved, but such description is not allowed by FIDE rules. These shortened forms are sometimes called minimal or abbreviated algebraic notation.

Disambiguating moves

When two identical pieces can move to the same square, the moving piece is uniquely identified by specifying the piece's letter, followed by :
  1. the file of departure ; or
  2. the rank of departure ; or
  3. both the file and rank of departure.
For example, in the diagram, Bb8 would be ambiguous, as either of the bishops on a7 and d6 could legally move to b8. The move of the d6 bishop is therefore specified as Bdb8, indicating that it was the bishop on the d file which moved. Although they could also be differentiated by their ranks, the file letter takes precedence.
For the black rooks both on the 8th rank, both could potentially move to f8, so the move of the d8 rook to f8 is disambiguated as Rdf8. For the white rooks both on the a file which could both move to a3, it is necessary to provide the rank of the moving piece, i.e., R1a3.
In the case of the white queen on h4 moving to e1, neither the rank nor file alone are sufficient to disambiguate from the other white queens. As such, this move is written Qh4e1.
As above, an "x" can be inserted to indicate a capture; for example, if the final case were a capture, it would be written as Qh4xe1.

Pawn promotion

When a pawn moves to the last rank and promotes, the piece promoted to is indicated at the end of the move notation, for example: e8Q. Sometimes an equals sign or parentheses are used: e8=Q or e8, but neither format is a FIDE standard. In Portable Game Notation, pawn promotion is always indicated using the equals sign format.
In older books, pawn promotions can be found using a forward slash: e8/Q.

Draw offer

In FIDE Laws of Chess, an equals sign with parentheses, "", is used to write the offer of a draw on the next to a move, but this is not part of algebraic notation.

Castling

is indicated by the special notations 0-0 and 0-0-0.
While the FIDE Laws of Chess uses the digit zero, PGN requires the uppercase letter O.

Check

A move that places the opponent's king in check usually has the symbol "+" appended. Alternatively, sometimes a dagger or the abbreviation "ch" is used. Double check is commonly indicated the same as check, but is sometimes represented specially as "dbl ch", or in older books as "++". Some publications indicate a discovered check with an abbreviation such as "dis ch". The Encyclopedia of Chess Openings omits any indication of check.

Checkmate

at the completion of moves can be represented by the symbol "# ". The word mate is commonly used instead. Occasionally the double dagger is seen. A checkmate is represented by "≠" in the macOS chess application. In Russia and ex-USSR, where captures are indicated by ":", checkmate can also be represented by "X", "x", or "×".

End of game

The notation 1–0 at the completion of moves indicates that White won, 0–1 indicates that Black won, and ½–½ indicates a draw. In case of forfeit, scores 0–0, ½–0 and 0–½ are also possible. If player lost by default, results are +/−, −/+ or −/−.
Often there is no indication regarding how a player won or lost, so simply 1–0 or 0–1 may be written to show that one player resigned or lost due to time control or forfeit. Sometimes direct information is given by the words "White resigns" or "Black resigns", though this is not considered part of the notation but rather a return to the surrounding narrative text.

Notation for a series of moves

A game or series of moves is generally written in one of two ways.
Moves may be interspersed with commentary. When the resumes with a Black move, an ellipsis fills the position of the White move, for example:

History

Descriptive notation was usual in the Middle Ages in Europe. A form of algebraic chess notation that seems to have been borrowed from Muslim chess, however, appeared in Europe in a 12th-century manuscript referred to as MS. Paris Fr. 1173. The files run from a to h, just as they do in the current standard algebraic notation. The ranks, however, are also designated by letters, with the exception of the 8th rank which is distinct because it has no letter. The ranks are lettered in reverse – from the 7th to the 1st: k, l, m, n, o, p, q.
Another system of notation using only letters appears in a book of Mediaeval chess, Rechenmeister Jacob Köbel's Schachzabel Spiel of 1520.
Algebraic notation is described in 1847 by Howard Staunton in his book The Chess-Player's Handbook. Staunton credits the idea to German authors, and in particular to "Alexandre, Jaenisch and the 'Handbuch.

Piece names in various languages

The table contains names for all the pieces as well as the words for chess, check, and checkmate in several languages. NB: alfil is a chess-specific loanword from Arabic which has lost its original meaning of "elephant" in the European languages that use it for the piece called bishop in English.

Similar notations

Besides the FIDE standard algebraic notation already described, several similar systems are in use for their own particular advantages.

Figurine algebraic notation

Figurine algebraic notation is a widely used variation of algebraic notation which substitutes a piece symbol for the letter representing a piece, for example: ♞c6 in place of Nc6. This enables moves to be read independent of language.
The Unicode Miscellaneous Symbols set includes all the symbols necessary for FAN. In order to display or print these symbols, one has to have one or more fonts with good Unicode support installed on the computer, that the Web page, or word processor document, etc., uses.

Long algebraic notation

Some computer programs use a variant of algebraic chess notation termed long algebraic notation or fully expanded algebraic notation. In long algebraic notation, moves specify both the starting and ending squares. Sometimes it is separated by a hyphen, for example: e2e4 or Nb1-c3 with hyphen. Captures are still indicated using "x": Rd3xd7.
The long notation takes more space and thus is not as commonly used. However, it has the advantage of clarity, particularly for less-skilled players or players learning the game. Some books using primarily short algebraic notation use the long notation instead of the disambiguation forms described earlier.
A form of long algebraic notation is also notably used by the Universal Chess Interface standard, which is a common way for graphical chess programs to communicate with chess engines.

ICCF numeric notation

In international correspondence chess the use of algebraic notation may cause confusion, since different languages employ different names for the pieces; hence the standard for transmitting moves in this form of chess is ICCF numeric notation. In recent years, the majority of correspondence games have been played on on-line servers rather than by email or post, leading to a decline in the use of ICCF numeric notation.

PGN for computer storage

Chess games are often stored in computer files using Portable Game Notation,
which uses algebraic chess notation as well as additional markings to codify a game. As mentioned, PGN requires uppercase letter O to represent castling, while the FIDE Handbook uses digit zero.

Annotation symbols

Though not technically a part of algebraic notation, the following are some common symbols frequently used by annotators, for example in publications Chess Informant and Encyclopaedia of Chess Openings, to give evaluative comment on a move or position.
On moves:
On positions:
The symbol chosen is simply appended to the end of the move notation, for example: 1.d4 e5?! 2.dxe5 f6 3.e4! Nc6 4.Bc4+/−