fiftymove

Fiftymove, commonly called the fifty-move rule, is a chess rule that allows a game to be drawn if no pawn move or capture has occurred in the last fifty moves by both players. Here, a move refers to a single turn by one player, and the count covers fifty full moves in total (White and Black combined).

The fifty-move rule is reset whenever a pawn is moved or a capture takes place. After such an event, the fifty-move counter starts anew from zero, and the clock continues from there regardless of any other piece moves.

Enforcement and practice: the draw is not automatic. Either player may claim the draw with the arbiter when the condition has been met, typically on the player’s turn. In official competition, the arbiter verifies the move history and, if appropriate, declares the game drawn. The rule is codified in the Laws of Chess as adopted and maintained by FIDE, the international governing body of chess.

History and context: the fifty-move rule was introduced to prevent endless and non-progressing endgames, particularly in rook and minor-piece endings where neither side can force a pawn promotion or a capture. It remains a standard element of modern chess rules and is used alongside other draw mechanisms, such as agreement between players and the threefold repetition rule.