Connect Four
How to play Connect Four
- Choose the computer's strength, or Another person to play on the same screen.
- Click a column to drop your counter into it. It falls to the lowest empty square.
- Get four of your colour in a row, in any direction, before your opponent does.
Frequently asked questions
Who wins Connect Four if both players play perfectly?
The first player, with the right opening. Connect Four was solved in 1988: starting in the middle column wins, and every other opening either draws or loses.
Why is the middle column so strong?
Because more lines of four pass through it than through any other column. The computer here adds a small bonus for the centre for the same reason.
How does the computer play?
It looks several moves ahead and scores each position by the lines each side could still complete, counting threes far more than twos. Easy looks one move ahead and plays at random some of the time; medium looks four moves ahead and hard six.
Can I take a move back?
Yes. Undo steps back one move against another person, and takes back the pair of moves against the computer so it is your turn again.
How do I stop losing to the computer?
Watch for your opponent having three in a row with an empty square at either end, and block it before anything else. Then look for moves that give you two threats at once, because only one can be blocked.
Are my results saved?
Your wins, draws and losses are kept in this browser only.