Tic-Tac-Toe
The timeless duel of X's and O's. Simple to learn, sharp to master — now with online play and its own rankings.
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The rules, in four steps.
- Players take turns placing their mark (X or O) on the 3×3 grid.
- Line up three of your marks in a row — horizontal, vertical, or diagonal — to win.
- The centre and corners are the strongest opening squares.
- If the grid fills up with no three-in-a-row, the game is a draw.
Noughts and crosses, rated
Everyone knows tic-tac-toe. On Duelto it is played one on one against a real opponent, with a rating that rises and falls with every result, or against the bot when you just want a quick game.
Between two careful players the game is a draw. Winning means spotting the moment your opponent is not careful.
How to play well
- The centre square sits on four possible lines — more than any other square. The corners sit on three, the edges on two.
- Always check whether your opponent has two in a row before making your own move.
- The strongest attack is a fork: one move that makes two lines of two at once. Your opponent can only block one.
- If your opponent opens in a corner, take the centre. If they take the centre, take a corner.
Questions
Can tic-tac-toe be won every time?
No. With perfect play from both sides the game is always a draw, so wins come from your opponent’s mistakes.
Can I play against the computer?
Yes. The bot is there for quick games and practice, and bot games do not change your rating.
Is it free?
Yes. Every game on Duelto is free to play, with no ads inside the game and nothing to buy.
Do I need to download anything?
No. Duelto runs in the browser on a phone, tablet or computer. A free account, made with an email address, is all you need.
Can children play?
Duelto is open from age 8. Accounts for players under 13 are activated by a parent through the confirmation email, and run with extra restrictions.
Other games on Duelto
- RPS Board — Arrange 14 pieces, capture the flag. Rock-paper-scissors decides every fight.
- Classic RPS — Pure rock-paper-scissors — best of 5. Read your opponent, win the duel.
- BattleShield — Shield, reload, or fire — at the same time as your opponent. A 10-second showdown each round.
- Nim — Take turns removing stones; whoever takes the last one wins. A maths game with a secret to find.