Tactic

What Is a Pin in Chess?

A pin is when a piece cannot move without exposing a more valuable piece behind it on the same line.

Definition

A pin happens when a bishop, rook or queen attacks a piece that has something more valuable directly behind it on the same rank, file or diagonal. If the pinned piece moves, the valuable piece behind it is captured. When the piece behind is the king, the pinned piece cannot legally move at all — that is an absolute pin. When it is a queen or rook, moving is legal but usually costly, which is a relative pin.

Example

White plays Bg5 while Black's knight sits on f6 and queen on d8. The knight is pinned to the queen: if it moves, Bxd8 wins the queen. White can now pile more attackers onto f6 — with e5 or Nd5 — knowing the knight cannot run.

How to spot it

  • Look for enemy pieces lined up on the same rank, file or diagonal with the valuable one behind.
  • A pinned piece is a frozen target — attack it again rather than capturing immediately.
  • Pinned pieces are terrible defenders: they may not legally be able to recapture.
  • Watch for your own pieces being pinned before you rely on them to defend something.

The mistake most players make

Treating a pinned piece as if it still defends what it used to. An absolutely pinned knight cannot recapture at all, so a square it 'guards' may be completely undefended in practice.

Frequently asked questions

What is a pin in chess?

A pin is when a piece cannot move without exposing a more valuable piece behind it. Only bishops, rooks and queens can create pins, because only they attack along lines. If the piece behind is the king, moving the pinned piece is completely illegal.

What is the difference between an absolute pin and a relative pin?

In an absolute pin the piece behind is the king, so the pinned piece cannot legally move at all. In a relative pin the piece behind is merely valuable — moving is legal but usually loses material.

How do you break a pin?

There are four ways: move the valuable piece out of the line, block the line with another piece, capture the pinning piece, or attack the pinning piece so it has to move. Creating a bigger threat elsewhere can also work.

Related terms

  • Skewer — A skewer attacks a valuable piece so that when it moves away, a less valuable piece behind it is captured.
  • Fork — A fork is a single piece attacking two or more enemy pieces at the same time, so the opponent can only save one.
  • Battery — A battery is two or more long-range pieces stacked on the same line so their power combines.
  • Overloaded piece — An overloaded piece is defending too many things at once, so attacking one of its jobs wins the other.

Practise this pattern

Definitions stick once you have seen the pattern in a real game. Solve tactics puzzles to train recognition, review one of your games to find where it came up, or ask the coach to explain it in a position you are looking at.