A pin in chess is an attack by a bishop, rook or queen on a piece that cannot move away without exposing a more valuable piece behind it on the same line. If the piece behind is the king, it is an absolute pin: the pinned piece is not allowed to leave the line at all. If the piece behind is a queen or rook, it is a relative pin: the pinned piece can legally move, but doing so loses material. Only the three line pieces can pin, because only they attack along lines.
Chess pin meaning: an absolute pin, step by step
The white bishop on b5 pins Black's knight on c6 to the king on e8. The knight is frozen, so White simply attacks it again with a pawn.
4k3/pp3ppp/2n5/1B6/3P4/8/PP3PPP/6K1 w - - 0 1
Open this position in the analysis board →
After 1.d5, Black has exactly 13 legal moves, and not one of them is a knight move: moving the knight would leave the king in check from b5. The pawn takes on c6 next move, and White is a piece up. Stockfish 17.1 at depth 20 picks 1.d5 as the best move, at about +4.9.
That is the core idea of a pinned piece: it still exists, but it cannot do its job. Attack it with something cheaper, and it falls.
Absolute pin vs relative pin
| Type | Piece behind | Can the pinned piece move? |
|---|---|---|
| Absolute pin | King | No. Moving it off the line is illegal. |
| Relative pin | Queen, rook or another valuable piece | Yes, but the piece behind is then lost. |
A relative pin is a threat, not a rule, and that difference matters. The opening trap below, known as Légal's mate, shows a relative pin being broken on purpose.
Start
Black's bishop on g4 pins the f3 knight to the white queen. White ignores the pin with 5.Nxe5, offering the queen. After 5...Bxd1, the knights and bishop deliver checkmate in two. Black's correct reply is 5...dxe5, and Stockfish 17.1 at depth 20 still rates White better, at about +1.7, because 6.Qxg4 takes the bishop and White comes out a pawn up. The lesson: never trust a relative pin without checking what the pinned piece can do if it moves.
Which piece pins most often?
We checked all 52 pin puzzles in our trainer, which come from the Lichess puzzle database. In 32 of them, the solver's side has a bishop, rook or queen pinning a non-pawn piece, either in the starting position or after one of the solver's moves. For each, we recorded the first such pin.
| Pinning piece | Puzzles | Share |
|---|---|---|
| Rook | 14 | 44% |
| Queen | 12 | 38% |
| Bishop | 6 | 19% |
Of those 32 pins, 28 (88%) were absolute pins against the king, and the most common pinned piece was the queen (14 puzzles). In 22 puzzles the solver created the pin with a move; in the other 10 it already existed and the solution exploited it.
Method: we replayed each puzzle with the chess.js move generator and scanned every line from the solver's bishops, rooks and queens for an enemy piece with the king or a more valuable piece directly behind it. We ignored pawns as pinned pieces, which is why 20 puzzles are left unclassified. It is a sample of 52 puzzles, but the pattern is clear: look along open files and ranks for rook pins first, and always check whether a queen stands in front of its own king.
Pins and forks
Pins and forks work together. A pinned piece cannot escape, so it is a perfect second target for a fork. A pinned piece also stops defending: a knight pinned to its king no longer guards the squares it attacks, so pieces it was protecting become loose. When you pin something, ask what it was defending.
When a pin does not work
A pin alone wins nothing if you cannot attack the pinned piece again. This is the first position without White's d-pawn, with Black to move.
4k3/pp3ppp/2n5/1B6/8/8/PP3PPP/6K1 b - - 0 1
Open the no-extra-attacker position →
The knight is still pinned, but it is defended by the b7 pawn and White has nothing else to hit it with. Black calmly plays 1...Kd7, and Stockfish 17.1 at depth 20 calls the position equal (about 0.0). Taking on c6 only trades a bishop for a knight. A pin is pressure; it becomes a win only when you pile up more attackers than the defender has guards.
How to spot a pin in your games
Run this check whenever two enemy pieces share a line with nothing between them:
- Find the lines. Look at every file, rank and diagonal that contains the enemy king or queen.
- Find the front piece. Is there exactly one enemy piece between that king or queen and an empty stretch of board?
- Bring a line piece. Can your bishop, rook or queen reach that line with tempo, ideally where it cannot be captured?
- Pile on. Attack the pinned piece again, preferably with a pawn, before your opponent can unpin.
And the defensive view: when your king and queen, or king and rook, sit on the same open line, move one of them before your opponent puts a piece in between.
Practice: Pin
All 52 pin puzzles →Frequently asked questions
Can a pinned piece move?
It depends on the pin. In an absolute pin (to the king), the piece may only move along the pin line, for example a pinned rook sliding toward or capturing the pinning rook. Any move off the line is illegal. In a relative pin, the piece can move anywhere, but the piece behind it is then exposed.
Can a pinned piece give check?
Yes. A piece pinned to its own king still attacks the squares it normally attacks, so it still gives check to the enemy king. The king cannot step onto a square it covers, A check from a pinned piece is a real check.
How do you break a pin?
Four ways: move the piece behind out of the line (for example, the king steps aside), block the line with another piece, attack or capture the pinning piece, or add defenders to the pinned piece so winning it costs too much. In a relative pin you can also move the pinned piece with a bigger threat, as in Légal's mate.
What is the difference between a pin and a skewer?
They are the same line attack in reverse. In a pin, the less valuable piece is in front and the valuable one is behind. In a skewer, the valuable piece is in front, it must move, and the piece behind it is captured.
Ready for practice? The pin puzzles page has all 52 pin puzzles, from beginner to advanced, and the analysis board lets you test any pin you find in your own games. Next, see how a pinned line turns into a discovered attack.