How to win at Four in a Row: rules, the centre column, and the double threat

Four in a Row looks like a children’s game and plays like a chess puzzle. The rules take ten seconds to learn. Winning consistently takes an understanding of a few ideas that most casual players never notice: why the middle column matters so much, why some empty squares are worth more than others, and how to create a position where your opponent cannot stop you no matter what they do.

This guide covers all of it. You can play along in our free Four in a Row — it is a two-player game for one screen, so grab someone to test these ideas on.

#The rules

The board has seven columns and six rows. Players take turns dropping one disc into any column that is not full, and the disc falls to the lowest empty space in that column. The first player to get four of their own discs in a straight line — across, up and down, or diagonally — wins. If the board fills up with no line of four, the game is a draw.

That falling rule is the whole game. Unlike noughts and crosses, you cannot place a disc anywhere you like: you can only ever play the lowest free square of a column. Every piece of strategy below comes from that one constraint.

#The first player has the advantage

This is not an opinion. In 1988 two researchers, James D. Allen and Victor Allis, independently solved the standard seven-by-six game by computer. With perfect play, the first player can always force a win — but only by starting in the centre column. Start anywhere else and perfect play from the second player turns it into a draw or a loss.

You and your friend are not going to play perfectly, so the game is very much alive. But it tells you two practical things. If you go first, start in the middle. If you go second, you are defending, and your job for the first half of the game is to stop your opponent building rather than to race them.

#Own the centre

The middle column is involved in more possible lines of four than any other. A disc in the centre can be part of a horizontal line extending to either side, a vertical line, and diagonals in both directions. A disc in an edge column can only reach in one direction horizontally, so it takes part in far fewer lines.

Count them and the pattern is clear: squares near the middle of the board sit on more potential winning lines than squares near the edges. That makes centre squares more valuable, and it gives you a useful rule of thumb when you have no better move: play as close to the middle as you safely can.

#Threats, and why they are not all equal

A threat is an empty square that would complete a line of four for you if you could play there. Beginners think the goal is to make three in a row. The real goal is to make threats your opponent cannot deal with.

Because discs fall, a threat is only immediately dangerous if the square directly beneath it is already filled. A threat hanging in the air, with empty squares below it, cannot be played yet — but it has not gone away. It is waiting. And it changes how both of you can use the column underneath it.

#Never play directly under your opponent’s threat

This is the most common way games are thrown away. Suppose your opponent has a threat in the fourth row of a column, and the third row of that column is empty. If you drop a disc into that column, it lands in the third row — and now the square above it, their threat, is playable. They take it and win.

So before every move, ask: what does this disc make available directly above it? If the answer is a square where your opponent completes four, do not play there, even if the move looked good for other reasons.

#The double threat: how games are actually won

Your opponent can only drop one disc per turn. If you ever create two immediately playable threats at the same time, they can block one, and you play the other. That is the move that wins most games between decent players.

The classic shape is a horizontal three with both ends open on a row that is already supported underneath: you threaten to complete four on either side, and there is no single move that stops both. Another common one pairs a horizontal threat with a diagonal threat that share nothing, so blocking one leaves the other untouched.

Double threats rarely appear by accident. You build toward them by placing discs that each extend more than one potential line at once. That is another reason centre discs are strong: they tend to serve two or three lines simultaneously, which is exactly what you need to set up a fork later.

#Odd and even rows: the idea that decides the endgame

This is the deepest idea in the game, and the one that separates good players from strong ones. Number the rows one to six from the bottom. Late in the game, when most columns are filling up, players can run out of safe moves — every column they could play in would hand their opponent a winning square. Who gets squeezed first depends largely on which rows the threats are on.

Allis described the pattern precisely. Because there are 42 squares and the first player always moves on odd-numbered turns, the parity of the board tends to work out so that the first player benefits from threats on odd rows (1, 3, 5) and the second player from threats on even rows (2, 4, 6). A first-player threat on the third row, left unplayable underneath, often becomes decisive when the board fills and the second player is forced to move beneath it.

You do not need to calculate this exactly to use it. Just remember the rule when you are choosing between two threats to build: if you went first, prefer the one on an odd row; if you went second, prefer the one on an even row.

#A simple checklist for every move

• Can I win right now? Look for any square that completes four for you.
• Can they win next turn? If they have an immediately playable threat, block it.
• What does my move make available directly above it? Never open a square they can win on.
• Does this move build two lines at once, ideally near the centre?
• Is there a threat I can leave hanging in the air on a row that suits me?

Run through that in order and you will stop losing games you should have drawn, and start winning games you used to lose. The first two questions alone fix most beginners’ mistakes.

#Practise, and then branch out

The best way to get good is to play the same opponent repeatedly and talk about the games afterwards: where was the move that lost it? Swap who goes first each game, since the first player’s edge is real. When you want something with similar thinking but a different feel, try checkers, Reversi or chess. Our board games category and two-player category have plenty more.