Standard Algebraic Notation

Standard Algebraic Notation, abbreviated SAN, records each legal move in a compact form. Every square has a fixed coordinate: the file, meaning column, is a letter from a to h, and the rank, meaning row, is a number from 1 to 8 counted from White's side. SAN is the most common short form of algebraic notation.

In PGN, Portable Game Notation, a text format for storing games, pieces use the English initials K, Q, R, B, and N for king, queen, rook, bishop, and knight. A pawn has no letter. Handwritten scoresheets in other languages may use local initials, but machine-readable PGN SAN uses the English letters.

Reading a move

• e4 means that a pawn moves to e4. The absence of a piece letter identifies it as a pawn move.
• Nf3 means that a knight moves to f3.
• Bxe6+ means that a bishop captures on e6 and gives check, so the opposing king is under attack.
• e8=Q means that a pawn reaches the last rank and promotes, becoming a queen.
• O-O and O-O-O represent castling, the special king-and-rook move on the kingside or queenside. PGN SAN uses the letter O.

SAN adds origin information only when necessary. If two knights can move to d2, Nbd2 identifies the one starting on the b-file. This disambiguation prevents one string from naming two legal moves. Long Algebraic Notation and coordinate notation show the origin more routinely.

The # symbol marks checkmate, a position in which the king is attacked and has no legal reply. SAN describes one move inside a known position; an isolated string such as Nf3 is not enough to reconstruct the whole board.