Tic-tac-toe
How to play Tic-tac-toe
Get three in a row on a 3x3 grid.
About Tic-tac-toe
Tic-tac-toe is played on a 3x3 grid, and three marks in a row across, down or diagonally win.
A full grid with no line is a draw, and with perfect play every game is a draw.
Against the computer it is played as the best of five, and the players swap marks after every game.
The goal of Tic-tac-toe
Tic-tac-toe is played by two players, one marking X and the other O, who take turns marking an empty cell. The first to complete a line of their marks wins the game. Here you play against a computer player, a friend on the same device, or another person at an online table.
Against the computer the games make up a short series: the best of five on the 3x3 grid, the best of three on the 5x5 grid, and a single game of Ultimate Tic-tac-toe.
How to set up Tic-tac-toe
Tic-tac-toe is played on an empty 3x3 grid, and Tic-tac-toe 5x5 on an empty 5x5 grid. Ultimate Tic-tac-toe is played on nine 3x3 boards set out in a 3x3 grid of their own.
X always moves first. Who plays X in the first game is drawn by lot, and in each game after that the players swap marks, so each starts in turn.
Tic-tac-toe rules
On your turn you mark one empty cell with your mark. There is no passing, and a mark stays where it is for the rest of the game.
In Tic-tac-toe a line is three marks in a row, across, down or diagonally. In Tic-tac-toe 5x5 a line is four marks in a row in any of those directions.
In Ultimate Tic-tac-toe the cell you mark decides where your opponent plays next: they must play in the small board that sits in the same position on the big grid as your cell does in its own board.
A small board is won by three in a row inside it, and a small board that fills up with no line is drawn. If you are sent to a board that is already won or full, you may play in any board that is still open.
How to win at Tic-tac-toe
The first player to complete a line wins the game. In Tic-tac-toe and Tic-tac-toe 5x5 a full grid with no line is a draw.
In Ultimate Tic-tac-toe you win by winning three small boards in a row on the big grid. A drawn small board counts for neither player, and the game is a draw when no board is left open and nobody has three in a row.
A series ends as soon as one player has won more games than the other can still catch up with. The player with more game wins takes the series, a drawn game counts for nobody, and equal wins make a drawn series.
Tic-tac-toe strategy tips
On the 3x3 grid, start in the centre or a corner. Both lead to a draw with perfect play, but a corner gives your opponent more ways to go wrong.
Block your opponent's two in a row before anything else, unless you can complete a line of your own at once.
Win with a fork: a move that makes two lines of two at once, so your opponent can block only one of them.
On the 5x5 grid, block an open three early. Three in a row with both ends empty can become four in two different ways.
In Ultimate Tic-tac-toe, think about where your move sends your opponent as much as about the cell itself, and avoid sending them to a board that is won or full, which lets them play anywhere.
In Ultimate Tic-tac-toe the centre board is part of four lines on the big grid, more than any other board.
Tic-tac-toe questions and answers
Who goes first in tic-tac-toe?
X always moves first. Here the first game's X is drawn by lot, and the players swap marks for every game after that, so each player starts every other game.
Can you always win tic-tac-toe?
No. On the 3x3 grid, if neither player makes a mistake, every game ends in a draw. You can only win when your opponent makes a mistake, most often by missing a fork.
What is the best first move in tic-tac-toe?
A corner or the centre. Both draw against perfect play, but after a corner only one reply, the centre, saves your opponent, so a corner gives them more ways to go wrong.
How do you win tic-tac-toe every time?
You cannot against a player who makes no mistakes, but you can against one who does. Make a fork, a move that threatens two lines at once, so that only one of them can be blocked.
How does Ultimate tic-tac-toe work?
It is played on nine small boards set out in a 3x3 grid. The cell you mark sends your opponent to the small board in the same position, and they must play there. Winning a small board claims it, and three claimed boards in a row on the big grid win the game.
What happens if you are sent to a board that is already won?
You may play in any small board that is still open. The same applies when the board you are sent to is full, and a full board with no line counts for neither player.
What is tic-tac-toe called in other countries?
In Britain it is called noughts and crosses. It is Tic-Tac-Toe in German, tres en raya in Spanish, morpion in French and krestiki-noliki, crosses and noughts, in Russian.
Can you play tic-tac-toe online with a friend?
Yes. Sign in, follow the Multiplayer link and open a table for two, choosing the board and a single game or the best of three or five, then send your friend its code or list the table in the lobby. A player who takes more than 45 seconds over a move has the computer move for them, and leaving the table ends the series, with the other player winning it.
Can you play tic-tac-toe with a friend on the same device?
Yes. Choose a friend as your opponent in the menu beside New game, and the two of you take turns on the same screen. Games against a friend are not recorded.
Can you beat the computer at tic-tac-toe?
At Easy and Normal, yes. Normal always takes a win and always blocks a line, but it does not see a fork coming. At Hard the computer never loses on the 3x3 grid, so the best you can do there is a draw. The menu beside New game sets the level.