What Is Pin in Chess?
A pin is a tactic where a piece is immobilized because moving it would expose a more valuable piece behind it to capture.
Definition
A pin occurs when an attacking piece threatens a defending piece that, if moved, would expose a more valuable piece behind it to capture. An absolute pin is when the pinned piece cannot legally move because it would leave its own king in check. A relative pin is when moving the pinned piece is legal but loses material.
Example
A White bishop on b3 pins a Black knight on e6 against the Black king on g8. The knight cannot legally move — it would expose the king to check. White can now attack the pinned knight with a pawn on d5, winning the knight for free.
Why It Matters for Your Chess
Pins are one of the most powerful strategic tools in chess. A pinned piece cannot defend other pieces effectively. Learning to create pins — and to escape or break them — is essential for any improving player.
Frequently Asked Questions
What is an absolute pin?
An absolute pin is when a pinned piece cannot legally move because doing so would expose its king to check. Moving the piece would be an illegal move.
What is a relative pin?
A relative pin is when moving the pinned piece is technically legal, but doing so would lose a more valuable piece behind it. The pin is 'relative' because the player can choose to ignore it — at a material cost.
Which pieces can create pins?
Only pieces that move in straight lines can create pins: bishops (diagonals), rooks (ranks and files), and queens (all directions). Knights and pawns cannot pin.
Practice Pin in Your Games
FireChess detects tactical patterns like pin in your games and shows you exactly what you missed — and how to find them next time.
Related Terms
Fork
A fork is a tactic where one piece attacks two or more enemy pieces simultaneously, forcing your opponent to lose material.
Skewer
A skewer is the reverse of a pin — a valuable piece is attacked directly and must move, exposing a less valuable piece behind it to capture.
Discovered Attack
A discovered attack is unleashed when one piece moves and unmasks an attack from a piece behind it — often winning material or giving check.
Tactic
A tactic is a sequence of forced moves that immediately wins material or delivers checkmate — the short-term 'violence' of chess.