About Tic Tac Toe
Tic Tac Toe is the game almost everyone learns first. Two players take turns marking squares on a 3x3 grid, and the first to line up three in a row wins.
Nine squares and eight winning lines sound trivial, but the game rewards clear thinking. Once you know how to take the center, block a threat, and set up a fork, you will never lose a game again.
Play Tic Tac Toe vs AI
The computer ranges from a beginner that misses simple threats up to a perfect player that can never be beaten, because Tic Tac Toe is a draw with best play.
Use the easier levels to practise spotting forks, then take on the hardest level and see if you can hold every game to a draw.
How to play Tic Tac Toe
Players alternate placing one mark on any empty square of the 3x3 grid. Marks stay where they are put and are never captured.
The first player to make a line of three across a row, down a column, or along a diagonal wins at once. A full board with no line is a draw.
Improve by learning strategy
Good Tic Tac Toe is about counting lines. The center touches four winning lines, each corner touches three, and each edge only two, which is exactly the order in which you should want those squares.
Winning comes down to the fork: one mark that opens two lines of two at the same time. Defending comes down to seeing that fork one move before it lands.
Frequently Asked Questions
No. Tic Tac Toe is a solved game, and perfect play by both sides always ends in a draw. You can only win if your opponent makes a mistake, which is why the computer on the hardest level can never be beaten, only held to a draw.
The center is the strongest opening because it lies on four of the eight winning lines. Corners are the next best, since each one covers three lines. Opening on an edge square is the weakest choice and gives your opponent the easiest path to an advantage.
No, but X does have the advantage of moving first and more ways to go wrong for O. Against a careless opponent X wins often. Against accurate defense the game is a draw, so competitive players alternate who plays X.
There are 255,168 distinct games if you count every legal sequence of moves, and 26,830 once you remove symmetries and stop at the winning move. Of those complete games, X wins the majority, O wins fewer, and the rest are draws.
They share the same core idea of lining up your marks, but the scale changes everything. Tic Tac Toe uses three in a row on a 3x3 grid and is fully solved, while Gomoku needs five in a row on a 15x15 board and stays deep enough for serious tournament play.
Similar games you might like
If you enjoy Tic Tac Toe, you will probably like these other abstract strategy board games.
Learn, Play, and Have Fun!
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