Build a Tic-Tac-Toe Game

What you’ll build

A fully working tic-tac-toe game that runs in your browser. Two players take turns clicking squares, it detects wins and draws, and has a restart button. All from a single prompt.

The prompt

Copy this entire block and paste it into any AI chatbot:

Create a complete, single-file HTML page with a tic-tac-toe game. Requirements:

- 3x3 grid of clickable squares, centered on the page
- Players alternate between X and O
- Display whose turn it is above the board
- Detect wins (3 in a row horizontally, vertically, or diagonally) and draws
- When someone wins, highlight the winning squares in green
- Show a "Play Again" button after the game ends
- Style it to look modern: use a dark background (#1a1a2e), white text, rounded squares with hover effects, and a clean sans-serif font
- Make it responsive so it works on mobile too
- All HTML, CSS, and JavaScript in a single file — no external dependencies

Output ONLY the complete HTML file, nothing else.

Where to paste it

Pick any of these — the prompt works on all of them:

• ChatGPT — Free tier works. After it generates the code, click the preview/artifact to play it directly.
• Claude — Free tier works. Claude shows an interactive artifact you can play immediately.
• Gemini — Free tier works. Copy the code and open it in your browser (instructions below).

How to run it

If the AI shows an interactive preview (ChatGPT and Claude usually do): just click it and play.

If you get raw code:

1. Select all the code and copy it
2. Open any text editor (Notepad, TextEdit, etc.)
3. Paste the code and save the file as tictactoe.html
4. Double-click the file — it opens in your browser and you can play

What just happened

You just built a working game without writing a single line of code. The AI understood your requirements, wrote the HTML structure, styled it with CSS, and programmed the game logic in JavaScript — all in seconds.

This is what people mean when they say “AI can code.” You describe what you want, and it builds it.

Try tweaking it

Now that you have a working game, try asking the AI to modify it:

• “Add a score counter that tracks wins for X and O”
• “Make it so I can play against the computer”
• “Change the colors to pink and purple”
• “Add sound effects when you place a piece”

Each of these is just another prompt away.