SAN

Standard Algebraic Notation

SAN is the standard compact notation used to record one legal chess move in its position.

SAN can include a piece letter, destination square, capture mark, disambiguation, promotion, castling, check, or checkmate. Its meaning depends on the current position.

The position decides whether SAN needs more detail

Standard Algebraic Notation is interpreted from the current position. Nf3 is meaningful only when the board tells us which knight can legally reach f3, whose turn it is, and whether extra disambiguation is needed.

Move either knight to f3 and see how SAN identifies it.

Both knights can reach f3, so SAN adds the starting file: Nef3 or Ngf3.

SAN adds only the information the move needs

A SAN move may contain a piece letter, starting-file or rank disambiguation, x for a capture, a destination square, a promotion choice, and + or # for the result. Pawn moves omit a piece letter.

e4: A pawn moves to e4.
R1e2: The rook on the first rank moves to e2.
exd8=Q+: The e-pawn captures on d8, promotes to a queen, and gives check.

Move annotations are separate from strict SAN

Symbols such as !, ?, and !? comment on move quality. They may appear beside SAN in annotated games, but they are not required to identify the legal move itself.