What is Tic-Tac-Toe?

Tic-Tac-Toe is a two-player strategy game where you place X's and O's on a 3x3 grid, trying to get three in a row before your opponent. Play against a friend or challenge the AI at different difficulty levels.

Two modes are included: pass-the-device 2-player or solo against an AI on easy, medium, hard, or expert. Expert plays a perfect minimax search and never loses — the best a human can do is force a draw. Hard is nearly as strong but slips now and then, so it stays beatable. Easy lets the AI miss obvious blocks so younger players can win. In 2-player mode each side can type a name, and a streak counter tracks consecutive wins. Score totals persist between rounds.

How to use

1. Choose your symbol (X or O) and select whether to play against a friend or the AI.
2. Tap any empty cell on the 3×3 grid to place your mark — players alternate turns.
3. Get three of your marks in a horizontal, vertical, or diagonal line to win the round.

When to use

• Killing five minutes in a queue or waiting room without installing an app.
• Teaching a child first-strategy thinking: corners beat edges, fork the board.
• Settling a quick coin-flip-style decision between two people in a fair way.

Result

You pick X and challenge the AI on Hard mode. You open in the center, the AI responds in a corner — after several moves, you manage a diagonal three-in-a-row to win.

FAQ

Is it actually possible to beat the AI?

On Expert, no. That tier runs minimax with full lookahead and never slips, so the best a human can manage is a draw. Hard plays the same search but mixes in the odd off-book move, which leaves it beatable if you set up a fork. Easy and Medium hand you plenty of openings.

What's the difference between Easy, Medium, Hard, and Expert?

Easy moves randomly except when it has an immediate winning move. Medium blocks your wins and takes its own when offered but won't plan two moves ahead. Hard runs the full minimax tree but occasionally plays a non-optimal move, so a sharp player can still catch it. Expert plays flawless minimax every turn and can't be beaten.

Why does the AI sometimes let me win on Easy?

Easy is intentionally weak so beginners and kids get to feel the win. It only reacts to threats one move away and ignores fork setups, which means a two-pronged trap usually beats it.

Can I choose to play as O instead of X?

Yes. In vs-AI mode the Play as selector lets you pick X or O. The opening move alternates every round, so neither side keeps the first-move edge across a session — one round you open, the next the other side does. Picking O still shifts the strategic problem from attack to defence, and the AI takes the opening whenever a round starts on its side. Changing sides resets the score so the Player and AI tallies stay unambiguous.

Does the score reset when I close the page?

The current session's tally stays on screen between rounds but isn't saved to disk. Reloading the page or coming back tomorrow gives you a clean scoreboard.

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