How to play Tic-Tac-Toe
Controls
You play X and always move first. Tap or click any empty cell to drop your mark. The AI, playing O, replies a moment later. A round ends when someone gets three marks in a row — across, down, or diagonal — or when all nine cells are filled with no winner. Press New round to deal a fresh board; Reset streak sets your win counter back to zero on purpose.
The objective
Beat the AI to grow your streak. Each consecutive win adds one. A loss or a draw resets the streak to zero. The streak itself is your "score" — the leaderboard tracks the longest you've ever managed in this browser. To make the game beatable, the AI picks a random legal move roughly 15% of the time; the rest of the time it plays optimal minimax.
Tips
- Take the center first when you can. It's part of four possible winning lines, twice as many as a corner.
- Build forks — two open winning threats at once force the AI to block one and concede the other.
- Defense beats offense. A missed block costs you the round; a missed attack only costs you a turn.
A little history
Tic-Tac-Toe is one of the oldest known games — ancient Roman boards have been excavated, and Egyptian versions go back to roughly 1300 BCE. It's also famously a "solved" game: two perfect players will always tie. That's why the AI's small random wobble is what makes a streak even possible.
Accessibility
Cells are real <button> elements with ARIA labels, so
keyboard users can Tab between them and Space/Enter to play. The board
layout grows to fill its column and uses high-contrast marks.