How to play
Tic Tac Toe, also known as noughts and crosses, is played on a grid of three rows and three columns. Two players take turns placing their mark, an X or an O, in an empty square. The first player to line up three of their own marks in a row, a column or a diagonal wins the round. If all nine squares are filled and nobody has three in a row, the round is a draw.
X always moves first. Choose vs Computer to play against the computer, and pick whether you want to be X (you move first) or O (the computer moves first). Choose 2 players to play with a friend on the same screen; in that mode the player who opens the round alternates each time you start a new one, so neither side keeps the first-move advantage.
Rules
- The board has nine squares. Each turn you place exactly one mark in an empty square.
- Marks never move and cannot be removed once placed.
- Three matching marks in a line win: there are eight possible lines (three rows, three columns and two diagonals).
- A full board without a winner is a draw.
Controls
- Mouse: click an empty square to place your mark.
- Touch: tap an empty square. The squares are large so they are easy to hit on a phone.
- Keyboard: use the arrow keys to move between squares and Enter or Space to place a mark. You can also press 1–9 to play a square directly; the keys follow the layout of a number pad, so 7 8 9 is the top row and 1 2 3 is the bottom row.
- Screen readers: every square has a name such as "Row 1, column 3, empty", and moves and results are announced.
Difficulty levels
- Easy: the computer mostly plays random moves. It notices a winning move about half of the time, so it is easy to beat.
- Medium: the computer takes a win when it can and blocks your winning move when it must, but otherwise plays at random. Set up a double threat to beat it.
- Impossible: the computer searches every possible continuation and always plays a best move. It wins as quickly as it can and loses as slowly as it can, but it cannot be beaten. Your realistic goal is a draw.
Tips and strategy
- Start in the centre or a corner. The centre is part of four lines and each corner is part of three, while an edge square is part of only two.
- Block immediately. If your opponent has two marks in a line with the third square empty, take that square unless you can win right now.
- Create a fork. A fork is a move that makes two separate winning threats at once. Your opponent can block only one, so you win. Against a player who does not know about forks, this wins most games.
- Stop their fork. If you are O and X starts in a corner, answering in the centre is the safe reply. Answering on an edge or in the opposite corner can lose against good play.
- With perfect play it is always a draw. If both players never make a mistake, nobody wins, which is why the Impossible level can only be drawn, not beaten.
Frequently asked questions
Can the Impossible computer really not be beaten?
Correct. Tic Tac Toe is a small game, and the computer examines every possible sequence of moves before it plays. The best you can do is draw.
Who goes first?
X always goes first. Against the computer, you choose whether you play X or O. In the 2-player mode the opening player switches every round.
Are my scores saved?
Yes. The scoreboard is stored in your browser separately for each mode and difficulty level, and the round in progress is saved too, so you can close the page and continue later. Use Reset scores to clear the scoreboard you are looking at.
Why does the computer wait before moving?
A short pause makes the game feel more natural. While the computer is thinking your input is locked so you cannot place a mark by accident. The pause is skipped if your device is set to reduce motion.
Does it work offline?
Once the page has loaded, it does not need an internet connection to play.
More free games
- Four in a Row – drop discs and line up four.
- Checkers – jump and capture your way across the board.
- Memory – match the pairs in as few moves as you can.
- Minesweeper – clear the field without hitting a mine.
- Sudoku – fill the grid with logic.
- Word Guess – find the hidden five-letter word.
- Snake – the classic arcade game.
- 2048 – slide and merge tiles.