Games & scoring / Two players
Tic-tac-toe: Play a Friend or the Computer
Play tic-tac-toe on a three-by-three board against a friend or the computer. Choose random easy play or unbeatable hard play, and go first or second.
Tic-tac-toe: Play a Friend or the Computer: Checks all eight winning lines after each turn. Easy mode picks a random empty square. Hard mode searches possible continuations and chooses an optimal move, so it never loses from a fresh game. Winning streaks and their local best are tracked for the chosen opponent and mark. Runs 100% locally in your browser with zero server file uploads.
- Category
- Health & sport tools
- Runs
- In your browser
- Cost
- Free · no sign-up
- Availability
- Ready to use
Runs entirely in your browser
Choose a square with a click, tap or Enter. Arrow keys move focus. Hard mode searches every continuation and cannot be beaten from a fresh game.
Rules and strategy
Win immediately if you can, then block an immediate opposing win. A fork threatens two different winning lines at once. The centre and corners often provide more ways to create or stop forks than an edge square.
A full board with no completed line is a draw. Perfect play from an empty board is a draw; hard mode plays for that result or a win if the other player makes a mistake.
History
Noughts and crosses became an early computer game in 1952, when Cambridge researcher Alexander Douglas made a version for EDSAC. The Computer History Museum's 1952 timeline documents it under the name OXO. Timeline: https://www.computerhistory.org/timeline/1952/. This board uses original CSS and text marks.
How to use it
- Choose a friend, an easy computer or a hard computer. Against the computer, choose X to go first or O to go second.
- Take turns placing marks in empty squares.
- Complete a row, column or diagonal of three marks to win. If all squares fill without a winner, the game is a draw.
Privacy & limitations
Your moves stay in your browser. Best streaks are saved locally on this device.
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Frequently asked questions
Can I beat hard mode?
From a fresh game, no. Correct play by both sides leads to a draw. Easy mode chooses random moves and can make mistakes.
Can two people use the same device?
Yes. Choose A friend, then alternate X and O on the same board.
How do I use the keyboard?
Use Tab to focus a square, arrow keys to move between squares and Enter or Space to place your mark.
Who moves first?
X always moves first. Choose O against the computer to let it begin.
Free tool · runs in your browser · no account required