Check (chess)

A check is a condition in chess, shogi and xiangqi that occurs when a player's king (or general in xiangqi) is under threat of capture on their opponent's next turn. A king so threatened is said to be in check. A player must get out of check, if possible, by interposing a piece between the threatening piece and the king, capturing the threatening piece, or moving the king to a square where it is no longer in check. If the player cannot move out of check, the game ends in checkmate and the player loses. Players cannot make any move that puts their own king in check.

A check is the result of a move that places the opposing king under an immediate threat of capture by at least one of the player's pieces. Making a move that checks is sometimes called "giving check". If the king is in check and the checked player has no legal move to get his king out of check, the king is checkmated and the player loses.

Under the standard rules of chess, a player may not make any move which places or leaves their king in check. A player may move the king, capture the threatening piece, or block the check with another piece.

Some variations of chess, such as Losing chess, allow a player to move into check, and in fast chess a player is permitted to leave their king in check, which results in them losing the game.

A king cannot itself directly check the opposing king, since this would place the first king in check as well. However a move of the king could expose the opposing king to a discovered check by another piece.

In informal games, it is customary to announce "check" when making a move that puts the opponent's king in check. However, in formal competitions, check is rarely announced.

There may be up to three possible ways to get a king out of a single check on the following move:

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