Shogi notation is the set of various abbreviatory notational systems used to describe the piece movements of a shogi game record or the positions of pieces on a shogi board.
A record of an abstract strategy board game such as shogi is called in Japanese.
Recording moves
Western notation
The system used in English language texts to express shogi moves was established by George Hodges and Glyndon Townhill in 1976 by the second issue of Shogi magazine. A slightly modified version was used in . It is derived from the algebraic notation used for chess, but differs in several respects. A typical move might be notated P86 (Hosking) or P-8f (Hodges). The notation format has the following 5 part structure:
{| style='margin: 30px;' ! style='padding-right: 55px;' | 1 ! style='padding-right: 55px;' | 2 ! style='padding-right: 55px;' | 3 ! style='padding-right: 55px;' | 4 ! 5 |- | style='padding-right: 55px; text-align: center;' | piece | style='padding-right: 55px;' | (origin) | style='padding-right: 55px;' | movement | style='padding-right: 55px;' | destination | (promotion)
An example using all 5 parts is S72x83+ or S7bx8c+. All parts are obligatory except for the origin and promotion parts. (Thus, most notation strings only contain 3 parts.) The origin part is only indicated when needed to resolve ambiguity. The promotion part is only needed when there is the possibility of promotion.
Western notation is not used in Japanese language texts, as it is no more concise than traditional notation with Japanese characters (kanji) and two ciphers which originated in the Edo period.
Piece
The first letter represents the piece moved. For instance, P is for Pawn. Below are the abbreviations used.
{| style='margin: 20px;' class="wikitable" ! Abbreviation !! English Term !! Japanese |- | P || pawn || |- | L || lance || |- | N || knight || |- | S || silver || |- | G || gold || |- | B || bishop || |- | R || rook || |- | K || king || /
Promoted pieces are indicated by a + preceding the letter. For example, +P is a promoted pawn ( tokin), +R is a promoted rook (that is, a dragon ).
Some Japanese websites (such as 81Dojo) and Japanese authors use two different abbreviations for the promoted rook and promoted bishop in a way more similar to Japanese notation. Thus, D (for dragon) instead of +R and H (for horse) instead of +B. Additionally, a promoted pawn can be encountered as T (for tokin) instead of +P.
Ambiguity resolution: Origin coordinates
In cases where the moving piece is ambiguous, the starting square is added after the letter for the piece but before the movement indication.
For example, in diagrams below, Black has three golds which can move to square 78. Thus, simply notating G-78 is not enough to indicate the move. The three possible moves are distinguished via the origin specification as G77-78, G68-78, or G79-78.
Movement type
Following the abbreviation for the piece is a symbol for the type of move. There are 3 different indications:
{| style='margin: 20px;' class="wikitable" ! Notation Symbol !! Movement Type |- | - || simple movement |- | x || capture (opponent's piece) |- | * or ’|| drop (your own piece)
As examples, P-24 indicates moving one's pawn to the 2d square (without capture), Px24 indicates moving one's pawn to the 24 square and capturing the opponent's piece that was on 24, and P*24 indicates dropping one's pawn in hand to the previously empty 24 square. (Note the x indication is a significant departure from Japanese notation, which has no way of signaling whether a piece was captured.)
There is some variation for the drop symbol. A * (asterisk) is often used, but some books (e.g. use a ’ (apostrophe) instead. Thus, Hosking B’56 is equivalent to Hodges B*5f.
The simple movement indication (the hyphen -) is not used by who does not use a movement symbol. Thus, Hosking P26 is equivalent to Hodges P-2f.
Destination coordinates
After the movement piece indication is the square on which the piece lands. This is indicated by a numeral for the file (1–9) and the rank (1–9), with 11 being the top right corner from Black's perspective and 99 being the bottom left corner. This is based on Japanese notation conventions.
Hosking differs from Hodges in that Hosking uses numerals for the rank notation whereas Hodges uses letters (a–i) for the rank.
Promotion status
If a move entitles the player to promote, then a + is added to the end if the promotion was taken or an = if it was declined. For example, Nx73= indicates an unpromoted knight capturing on 73 without promoting while Nx73+ indicates an unpromoted knight capturing on 73 and promoting. The promotion status is always omitted in situations where promotion is not possible. When promotion is possible, then the promotion status is obligatorily notated.
Other conventions
Game moves in western notation are always numbered (unlike Japanese game records). Additionally, what is numbered are pairs of two moves – the first move by Black, the second by White – instead of numbering each move by each player. This also differs from the Japanese system. For instance, three pairs of moves (or six individual moves) are numbered as 1.P-76 P-34 2.P-26 P-44 3.S-48 S-32. However, in the British Shogi magazine of the 1970s and 1980s, the pair number convention was not used for tsumeshogi problems, in which case the each player's move is number just as in the Japanese notation conventions.
Following western chess conventions, omitted moves are indicated with an ... ellipsis. As a consequence of the way moves are numbered in the western system, all moves by White are notated with an ellipsis prefix in texts. For example, ...P-55 indicates a move by White while P-55 indicates a move by Black. In handicap games, White plays first, so Black's first move is replaced by an ellipsis. For example, 1...G-32 2.P-76 G-72.
Unlike western chess, game states like check or checkmate are not typically notated. However, the use of question marks and exclamation points to indicate questionable and good moves, respectively, are occasionally used.
Japanese notation
The earliest way to indicate game records in Japan during the Edo period was to use descriptive sentences such as Open the bishop's diagonal, push the rook's pawn, close the bishop's diagonal and the like. Soon afterward, a notational system was developed which is mostly the same as what is used in the present day in Japan.
Current standard
In Japanese notation, the notation string has the following five-part format:
{| style='margin: 30px;' class="wikitable" ! style='padding-right: 55px;' | 1 ! style='padding-right: 55px;' | 2 ! style='padding-right: 55px;' | 3 ! style='padding-right: 55px;' | 4 ! 5 |- | style='padding-right: 55px;' | (player side) | style='padding-right: 55px;' | destination | style='padding-right: 55px;' | piece | style='padding-right: 55px;' | (movement) | (promotion)
A typical move is indicated like (equivalent to western P-86). An example that uses all five parts is (which could be either S72-83+ or S72x83+ in western notation). The player's side information is optional and the movement and promotion indications are only used in order to resolve ambiguity.
Player's side
It is common for the White (gote) and Black (sente) player to be indicated at the beginning of the notation string with either black and white triangles () or shogi-piece-shaped pentagons (), such as or . However, this is not obligatory: several books notate shogi moves without explicit indication of which player is making the moves. (See the adjacent image for an example.) In such cases, knowing which player the move refers to can be determined by the context in the book. This white/black convention is more common when the moves are not numbered (which is also optional to notate).
Destination coordinates
For the board's coordinates, the file is indicated with an Arabic numeral followed by the rank indicated with a Japanese numeral (instead of an Arabic number or letter like in the western system). For example, square 23 in Japanese notation is .
{| style="margin: 20px;" class="wikitable" ! Japanese numeral !! Japanese pronunciation !! Arabic equivalent |- | || ichi || |- | || ni || |- | || san || |- | || yon || |- | || go || |- | || roku || |- | || nana || |- | || hachi || |- | || kyū || |- | || dō or onajiku || same
Earlier (for instance, in the Edo period), only Japanese numerals were used for both file and rank coordinate.
There is also an abbreviatory convention: when a piece moves to the same coordinates as the previous move's piece (as in a capture), the position is simply indicated with (which is pronounced dō or onajiku) instead of the file-rank coordinate numbers. For example, if Black's pawn moved to a square in which White's pawn captured Black's pawn and then both players' bishops recaptured followed by a rook recapture, this could be notated as which would be equivalent to the western notation sequence 1.P-24 Px24 2.Bx24 Bx24 3.Rx24. always implies a capture (although not all captures will use , of course). In some cases where the coordinates may be forgotten by the reader (for instance, if its antecedent is separated by a page turn or several paragraphs of text), then the number coordinates will precede to aid the reader like this: . An alternate symbol is used instead of in older books.NDL Digital Collections - 指将棋定跡集
It is also possible to encounter Arabic numerals for both the file and rank coordinates, such as instead of .
Also, since Japanese is often written vertically from top to bottom, the notation may be written vertically as well with the top number indicating the file and rank number below the file number. Finally, in older books of the Edo period, the notation may be written from right to left (as is the case with traditional vertical writing) even when the notation is written horizontally. However, this older practice is not used in the modern period, where horizontally writing is read from left to right following European language traditions. (See the 1839 game record image below for such an example.)
Piece
Pieces are indicated with kanji (instead of letters as in the western system). The piece's kanji follows the piece's board coordinates. The following symbols are used.
{| style="margin: 20px;" class="wikitable" ! Japanese !! Western !! Japanese || Western |- | || P || || +P |- | || L || || +L |- | || N || || +N |- | || S || || +S |- | || B || || +B |- | || R || or || +R |- | || G || || K
Promoted pieces are indicated with a prefix except for the promoted pawn, promoted bishop, and promoted rook, which are , , , respectively.
The character for dragon can also be encountered as its shinjitai form as well.
is used instead of in some older texts.
In tsumeshogi, the character is used essentially as a variable that represents a piece of any value. It is used to indicate to an interposing piece (of any kind) that is placed between the king and the opponent's checking piece.
Ambiguity resolution: Movement description
When there is ambiguity in piece movement, there is a complex system of movement description using the symbols below. The movement descriptors consist of (a) a dropped piece indicator, (b) movement indicators, and (c) relative piece origin indicators.
{| style='margin: 20px;' class="wikitable" ! Movement notation !! Japanese Pronunciation !! Meaning |- | || utsu || dropped |- | || agaru || upward |- | || hiku || downward |- | || yoru || horizontally |- | || sugu || vertical forward (gold/silver only) |- | or || || upward (dragon/horse only; rare)
{| style='margin: 20px;' class="wikitable" ! Piece origin notation !! Japanese Pronunciation !! Meaning |- | || migi || right-hand side (going leftwards) |- | || hidari || left-hand side (going rightwards)