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Masuk

Checkmate symbol

Also known as: #

The # sign added to the move that delivers checkmate and ends the game.

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Explanation

The # sign is appended to a move that delivers checkmate. The king is attacked and no legal move can save it. The king cannot move to safety, no piece can capture the attacker, and the attack cannot be blocked when that type of attack allows a block.

Standard Algebraic Notation (SAN) is the system of piece letters and square names used by , a plain-text format for storing games. In SAN, # is the standard mate mark. Scoresheet notation from the International Chess Federation (FIDE) also permits , but other sources use that sign for double check, so # is less ambiguous.

# belongs to the final move; it does not replace . A complete record still ends with 1-0 or 0-1 according to the winner. By contrast, marks a check from which a legal defense exists.

Common confusions

Mate and result

# describes the final move; 1-0 or 0-1 declares the result of the whole game.

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# and ++

FIDE allows both for mate, but ++ also has another common meaning. PGN files use # as the standard form.

View term

Sources

  1. 1.FIDE Laws of Chess taking effect from 1 January 2023, FIDE
  2. 2.Appendix C. Algebraic Notation, FIDE Rules Commission
  3. 3.Standard: Portable Game Notation Specification and Implementation Guide, rec.games.chess contributors; coordinated by Steven J. Edwards

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