What Is a Double Check in Chess?

Why a double check is so powerful

Against a single check there are three defenses: move the king, block the check, or capture the checking piece. Against two checks at once, blocking or capturing can only deal with one of them, so the king has to move.

That means both checking pieces can stand on squares where they are attacked. In the example, the bishop on g5 is attacked by both the queen on e5 and the knight on e4, but Black never gets the chance to take it.

How double checks happen

A double check is a discovered check where the moving piece also gives check. The usual setup is a rook or queen on a line to the king, with a bishop or knight in front that can jump to a checking square.

When the enemy king has few flight squares, a double check is often mate or close to it. Queen sacrifices that drag the king onto the line, as in the example, are a common way to set one up.

How to avoid one

Keep your king off files and diagonals where an enemy long-range piece is hidden behind one of its own pieces, and keep some flight squares around it. A king with room to move survives a double check far more often.

Common questions