Queen versus pawn ending

In this ending, one side has a king and queen, while the other has a king and pawn. Promotion means moving the pawn to the final rank and replacing it, usually with a queen. The queen normally wins by stopping the pawn with checks and later capturing it, but some very advanced pawns can draw.

The normal winning method

The standard winning method is to check until the defending king must stand directly in front of its own pawn. While the king occupies that square, it temporarily blocks promotion. The queen side uses the gained time to bring its king closer, then repeats the process until the pawn can be captured without allowing a stalemate defense.

Central or knight pawn

The king blocks the central pawn

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The pawn sits behind its own king

The black king occupies d1 in front of the d2-pawn. The queen can continue checking while the white king has time to approach; the concrete conversion remains subject to tablebase verification.

The stalemate exceptions

Stalemate occurs when the player to move is not in check but has no legal move, so the game is drawn. This explains the best-known exceptions. When the pawn is one step from promotion, rook pawns on the outside a- and h-files and bishop pawns on the c- and f-files can draw if their king is correctly placed and the attacking king is too far away. A file is a vertical column of the board.

Rook pawn with stalemate resourceBishop pawn with stalemate resource

The rook-pawn corner

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King in the corner, pawn protected

With the black king on a1 and the pawn on a2, the king directly protects the pawn and occupies the corner. The white king is far away, so the drawing resource associated with this geometry must be checked locally.

Knight pawns on the b- and g-files and central pawns on the d- and e-files normally lose even when equally advanced. The file alone is not enough to decide the position, however. The locations of both kings, whose turn it is, and any immediate checks can change the result. A nearby attacking king can also defeat the stalemate defenses available to rook and bishop pawns.

Attacking king close enough

The attacking king is already close

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The black structure Ka1 and a2 is preserved, but the white king is now on c3 and controls b2.

The same corner, a different king

The black structure Ka1 and a2 is preserved, but the white king is now on c3 and controls b2. That proximity changes the geometry that the tablebase must evaluate.

1. The black structure Ka1 and a2 is preserved, but the white king is now on c3 and controls b2.