How to beat the computer at Connect 4
Connect 4 looks simple, but it has a lot of depth. With perfect play the first player can always win, which is why the very first move matters so much.
Here is what to play first, how to build threats the computer cannot stop, and the row rule that decides most close games.
Start in the middle
The middle column is part of more possible lines than any other, so it is the strongest place to play. If you go first, drop your first disc in the centre column. If you go second and your opponent takes the centre, play in the centre column on top of theirs, and stay near the middle after that.
The outer columns are the weakest. A disc in column 1 or 7 can only be part of a few lines.
Build a double threat
A single three-in-a-row is easy to block. The way to win is a double threat: two different squares where one more disc wins, so the opponent can only block one.
Look for ways to make two threes at once, especially across a diagonal and a row together. Build the second line while the first is still hidden.
Odd rows and even rows
Count rows from the bottom, starting at 1. The player who goes first tends to profit from threats on the odd rows (1, 3 and 5). The player who goes second tends to profit from threats on the even rows (2, 4 and 6).
As the board fills, the columns run out of safe moves and one player is forced to play underneath the other's threat. So try to get your threat on the right row for your colour, and play to deny your opponent theirs.
Never play under a winning square
If your opponent has a winning square directly above the spot you are about to fill, do not play there. Playing it hands them the win. Equally, if you have a winning square with an empty spot below it, the opponent cannot play that spot, so you can wait.
Watch the diagonals
Most beginners notice rows and columns and miss diagonals. Before every move, scan both diagonals through the squares around your last disc and theirs.
Use the review
After a game, the review shows the move where your winning chances changed and flags any move that threw away a win. Look at those first. It is usually one careless disc.
Frequently asked questions
Who wins at Connect 4 with perfect play?
The first player, if they start in the centre column. The second player can only draw or lose against perfect play, but in real games mistakes decide the result.
What is the best first move in Connect 4?
The centre column. It belongs to the most possible winning lines.
What are odd and even threats?
A threat is a square that would complete four. Rows are counted from the bottom. The first player usually wants threats on odd rows, the second player on even rows, because of how the columns fill up.
How do I beat the computer at Connect 4?
Take the centre, avoid giving the opponent a winning square above your move, and try to build two threats at once. Higher levels block single threats, so you need a double one.
Put it into practice
Start against Trevor, the friendliest opponent, and work your way up the ladder of ten computer players to Pete, the hardest. It’s free and works in your browser.
Play Connect 4 now