Attackers, Defenders, and Counting
Counting means counting attackers and defenders on a square. The side with more attackers than defenders usually wins the piece on that square.
Two attackers, one defender
Black pawn is on d6. White queen on d5 and White pawn on e5 both attack d6. Black pawn on e7 alone defends d6, so White wins the pawn.
FEN: 4k3/4p3/3p4/3QP3/8/8/8/4K3 w - - 0 1
a b c d e f g h
8 . . . . k . . . 8
7 . . . . p . . . 7
6 . . . p . . . . 6
5 . . . Q P . . . 5
4 . . . . . . . . 4
3 . . . . . . . . 3
2 . . . . . . . . 2
1 . . . . K . . . 1
a b c d e f g hOne attacker, two defenders
Black pawn is on d6. White pawn on e5 attacks d6. Black pawns on e7 and c7 both defend d6, so capturing loses material for White.
FEN: 4k3/2p1p3/3p4/4P3/8/8/8/4K3 w - - 0 1
a b c d e f g h
8 . . . . k . . . 8
7 . . p . p . . . 7
6 . . . p . . . . 6
5 . . . . P . . . 5
4 . . . . . . . . 4
3 . . . . . . . . 3
2 . . . . . . . . 2
1 . . . . K . . . 1
a b c d e f g hCounting before capturing
White queen is on d5 and Black pawn is on d6. Before capturing, White counts one defender on d6 and two attackers, so the capture wins a pawn.
FEN: 4k3/4p3/3p4/3QP3/8/8/8/4K3 w - - 0 1
a b c d e f g h
8 . . . . k . . . 8
7 . . . . p . . . 7
6 . . . p . . . . 6
5 . . . Q P . . . 5
4 . . . . . . . . 4
3 . . . . . . . . 3
2 . . . . . . . . 2
1 . . . . K . . . 1
a b c d e f g hKey points
- An attacker is a piece that can capture on a square. A defender is a piece that can recapture on that square.
- Count attackers first. Then count defenders on the same square.
- If attackers outnumber defenders, capturing usually wins material.
- If defenders outnumber attackers, capturing usually loses material.
- Count in order of value. A small piece capturing first can change the count after each capture.
Try it Yourself
Edit the code, then press Run.
Running is simulated · Rust Playground
Exercise
A square has two White attackers and one Black defender. What usually happens if White captures?