Tic-tac-toe

You are X, the computer is O. Take turns choosing an empty square and make a line of three before your opponent does.

Difficulty
High score
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Play X against the computer’s O. Select an empty square. Three marks in a horizontal, vertical or diagonal line win. Easy plays randomly, Standard blocks threats, and Hard uses perfect play. A draw is a good result on Hard.

How to play
  1. Choose an empty square to place your X.
  2. Watch the computer’s O, and block a line of two.
  3. Make a line of three to win. If the board fills, the round is a draw.
Tips and tricks

A few ideas that make Tic-tac-toe easier and more fun:

  • The centre is the strongest opening, and the corners come next.
  • Look for a fork: one move that creates two lines of two at the same time.
  • Against the Hard computer, a draw is a great result. It never makes a mistake.
About Tic-tac-toe

Play Tic-tac-toe online

Also called noughts and crosses, this is the familiar three-by-three paper game. Three in a row wins. With careful play on both sides, the usual board can end in a draw.

Why it works

You look ahead, notice a threat and decide whether to attack or block. The small board makes planning and recognising patterns easy to practise in a short round.

These are the skills used during play; improvement outside the game is not established.