Tic-Tac-Toe Rules - How to Play
Tic-tac-toe is a short two-player game on a 3×3 grid. The rules decide legal moves and endings; choices such as blocking and making forks belong to strategy.
The board, marks, and first move
The board has nine empty squares arranged in three rows and three columns. One player uses X and the other uses O. On FreePlayBase, X starts each new game, then the players take turns. A mark, once placed, stays in that square.
Legal turns
- Choose any square that does not already contain X or O.
- Place your own mark in that square.
- Check whether that move has ended the game; otherwise the other player moves.
You may not overwrite a mark, move it later, or take two turns in a row. There is no gravity: any empty square is available.
How to win
A player wins immediately after placing three of their own marks in one straight line. The line can be horizontal across a row, vertical down a column, or diagonal from one corner to the opposite corner. Only matching marks count; a mixed line does not.
When the game is a draw
If all nine squares are filled and neither player has made a line of three, the result is a draw. No extra move is played. Blocking an opponent’s two-in-a-row is often wise, but it is not a formal rule: the rules allow any empty-square move until the game ends.
Rules example
Suppose X marks the top-left square, O marks the centre, and X marks the bottom-right square. X now has two diagonal marks, but has not won yet. If O leaves the top-right-to-bottom-left diagonal open, X may finish it on a later turn; O is still free under the rules to choose any empty square.
Tic-tac-toe rules FAQ
- Does X always move first on this board?
- Yes. Every new FreePlayBase tic-tac-toe game begins with X. Players can swap sides between games if they want to share the first-move advantage.
- Can a diagonal win in tic-tac-toe?
- Yes. Either corner-to-corner diagonal is a valid winning line, alongside the three rows and three columns.
- Can I place a mark on an occupied square?
- No. A turn must use an empty square. Existing X and O marks remain fixed for the rest of the game.
- What makes a tic-tac-toe game a draw?
- The game is drawn when all nine squares contain marks and neither player has completed a horizontal, vertical, or diagonal line of three.
Try the rules on a live board
Play a quick round, practice against the AI, use one device for two players, or create a room for an online opponent.