Chess forks: one move, two problems
The most common tactic in chess, and the one that wins the most material below master level, because the defender only ever gets one move.
- 120 positions in the course
- Difficulty 587–2298
- Section: Tactics
- 5 levels
What a fork is
A fork is a single move that attacks two or more enemy pieces at the same time. The opponent gets one move to answer it, so unless they can defend both, capture the forking piece, or produce a bigger threat of their own, one of the two is lost.
Every piece can fork, but the knight is the reason the pattern has a reputation. A knight attacks in eight directions at once, its attacks cannot be blocked, and it is the only piece that can attack a queen without the queen being able to take it back.
How to spot it
- Look for enemy pieces sitting a knight's move apart -- the king and queen on squares of the same colour is the classic one.
- Look for two pieces on the same rank, file or diagonal with a gap: a queen or rook landing in the gap forks both.
- Check every square your knight can reach in two moves, not one. Most forks in real games are set up a move before they are played.
- Undefended pieces are half a fork already. A fork on two defended pieces usually wins nothing; a fork on one loose piece and a king wins it.
Three forks to find
Three positions from the 120 in this skill, easiest first. The highlighted squares are the move your opponent has just played. Work it out before you open the answer.
Position 1
Black to move. Find the best move.
Show the answer
27.Rxd5 27...Ne3+ 28.Kc1 28...Nxd5
The line wins a rook. The forking piece attacks two things at once and the defender only gets one move, so the less valuable of the two targets is lost.
The position comes from an endgame of a real game, rated 587 for difficulty. The answer reaches a winning advantage.
Position 2
White to move. Find the best move.
Show the answer
31...b4 32.Ng6+ Rxg6 33.Rxg6
The line comes out 2 pawns ahead. The forking piece attacks two things at once and the defender only gets one move, so the less valuable of the two targets is lost.
The position comes from an endgame of a real game, rated 1310 for difficulty. The answer reaches a winning advantage.
Position 3
White to move. Find the best move.
Show the answer
34...Kxd8 35.Qd2+ Kc8 36.Qxg2
The line wins a piece. The forking piece attacks two things at once and the defender only gets one move, so the less valuable of the two targets is lost.
The position comes from an endgame of a real game, rated 1882 for difficulty. The answer reaches a clear advantage.
Defending against forks
The prevention is geometric, not tactical: keep your king and queen off squares of the same colour, do not leave two pieces on one diagonal with a hole in the middle, and be suspicious every time an enemy knight reaches your half of the board.
Once a fork is on the board your options are narrow. Capture the forking piece, defend the more valuable target and move the other, interpose if the fork is a line piece, or find a counter-check that buys the tempo back. Counting which of those exists before you allow the position is the actual defensive skill.
Questions people ask
What is a fork in chess?
A move that attacks two or more of the opponent's pieces simultaneously, so that only one of them can be saved. Any piece can do it, including a pawn and the king.
Why are knight forks so common?
Because a knight's attack cannot be blocked and no other piece can attack it back along the same line, and because a knight on a good square hits eight squares of the opposite colour at once -- which makes a king and queen on the same colour a permanent liability.
What is a royal fork?
A fork that hits both the king and the queen. The check must be answered first, so the queen is lost unless the forking piece can be captured. It is almost always a knight.
How do I avoid getting forked?
Keep the king and queen on different-coloured squares, avoid lining major pieces up with a gap between them, and check what squares an enemy knight can reach in two moves before you commit a piece to a square it can hit.
Nearby patterns
Forks sits in Tactics. The rest of that section:
Tell it apart from its neighbour
Forks is confused with these more often than anything else, and the difference is usually one sentence long.
Printable worksheetsThree free PDF sheets of these positions with a full answer key. No sign-up, print and copy as many as you like.