Tactics
Knight Forks and Double Attacks
A double attack is a single move that creates two threats at once. Your opponent can usually answer one threat, but not both, so something falls. The fork is the most common version: one piece attacks two enemy pieces at the same time. Knights are famous for it, but queens, pawns, bishops, rooks and even kings can fork. If you learn to see forks quickly, you will win more material than almost any other single skill can give you at club level.
Why double attacks work
Chess is a game of one move at a time. When you make one threat, your opponent spends their move dealing with it. When you make two threats, they still only get one move. The defender has a few escape hatches: they can move one piece so that it protects the other, they can answer with a check or a bigger threat of their own, or they can capture the forking piece. Before you play a fork, check those three escapes. If none of them works, the fork wins material.
The ideal targets are pieces that are undefended (coaches call them loose pieces) and the king. A check is the strongest half of a double attack because the opponent has no choice: they must deal with the check first, and the other attacked piece is lost.
The knight fork
The knight is the classic forking piece for two reasons. First, it jumps, so it cannot be blocked. Second, no other piece attacks the way a knight does. When a knight attacks a queen or a rook, that queen or rook cannot attack the knight back. A bishop forked by a bishop can often capture the forker; a queen forked by a knight never can.
The most dramatic version is the royal fork, where the knight checks the king and attacks the queen, or the family fork, where it hits king, queen and rook together. Even a simple king-and-rook fork usually decides the game.
In the diagram, White plays 1.Nxc7+. The knight captures a pawn, checks the king on e8, and attacks the rook on a8 at the same time. Black's only legal replies are king moves (Kd7, Kd8 or Ke7), and after any of them White plays 2.Nxa8 and wins a full rook. Notice the pattern: the c7 square sits exactly one knight jump from both e8 and a8. Squares like c7 and c2 are classic forking squares because the king and queen-side rook start the game within a knight's reach of them.
A real opening example
The Fried Liver Attack shows a knight fork appearing straight out of the opening. After 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 d5 5.exd5 Nxd5 6.Nxf7, White's knight on f7 attacks both the queen on d8 and the rook on h8. Black usually answers 6...Kxf7, giving up the right to castle and walking into a strong attack after 7.Qf3+. The knight is sacrificed, but the double attack is what makes Black's choice so unpleasant.
Play through the Fried Liver knight fork →
Queen forks
The queen moves like a rook and a bishop combined, so she can attack in up to eight directions at once. That makes her the most frequent forker in practical games, especially when the enemy king is exposed and the opponent has loose pieces on the edge of the board.
Here White plays 1.Qd5+. The queen checks the king on g8 through e6 and f7, and at the same time looks down the long diagonal at the rook on a8. Black has nothing to block with and must move the king to f8 or h8, after which 2.Qxa8 wins the rook. The reason it works is simple: the rook on a8 is undefended. If Black's rook had been protected, the fork would have been harmless.
Queen forks most often appear after a check on an open diagonal or file, and they are a common way that endgames with queens on the board are decided. Whenever the enemy king is on an open line and some piece is loose, ask whether one queen move can hit both.
Pawn forks
The humble pawn is an excellent forker because it is worth the least. If a pawn attacks two pieces, the opponent cannot even trade it off favorably, since capturing a pawn with a piece rarely solves anything when another piece is still hanging.
In this simple position, 1.e5 attacks the knights on d6 and f6 simultaneously. Black can save one knight, but White captures the other next move. In real games the pawn fork usually appears in the center, where a pawn push from e4 to e5 or d4 to d5 hits two minor pieces that have been developed side by side. It also appears in the opening as the so-called fork trick, where a player gives up a piece briefly and regains it with a pawn fork.
Other double attacks
A fork is not the only way to make two threats. A single move can also create one direct attack and one threat of mate. For example, a queen move that attacks a loose bishop while also threatening checkmate on h7 is a double attack, even though only one piece is being directly hit. Discovered attacks are another kind of double attack, because the moving piece and the unmasked piece each create a threat. Our guide to discovered attacks covers that family in detail.
Kings can fork too, especially in endgames. A king that walks forward and attacks two undefended pawns, or a pawn and a knight, is performing a fork just like a knight would.
How to spot forking squares
Forks do not appear by magic. Experienced players find them with a short routine:
- List the loose pieces. Look at every enemy piece and ask whether it is defended. Loose pieces and the king are your targets.
- Find pairs of targets. Pick two targets and look for a square that attacks both. For knights this is easier than it sounds: two pieces that sit a knight's distance from the same square, such as a king on e8 and a rook on a8 sharing c7, form a forkable pair.
- Ask if you can reach that square. Can a knight, queen or pawn get there in one move? If it takes two moves, can the first one be a check, so the opponent has no time to react?
- Check the forking square is safe. If the opponent can simply capture your forking piece with something cheap, the fork may not work. If the forking piece is a knight and the square is defended only by a queen or rook, the trade may still favor you.
A helpful knight-specific trick is to remember that a knight always lands on a square of the opposite color. If the king and the queen stand on the same color, a knight fork against them must come from a square of the other color. That narrows your search immediately.
Defending against forks
The same routine works in reverse. After your opponent's move, look at where their knights can jump next turn, and make sure your king, queen and rooks are not sitting on a shared knight square. Keep pieces defended where possible, because a fork of two protected pieces is rarely a fork at all. Many forks start with a check, so ask which checks your opponent has before you relax.
How to practise this
- Solve ten tactics a day on our puzzles page; forks are among the most common themes, and repetition builds the pattern memory you need during games.
- Set up a knight on an empty board in the analysis board, then place two enemy pieces and find every square that forks them.
- In your own games, after every opponent move, spend two seconds asking which pieces are loose on both sides. Most forks are found or missed in that question.
- Try fast puzzle rush rounds once the basic patterns feel familiar, so that spotting forks becomes quick and automatic.