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Tutorials / Beginner

Vibe Code a Browser Game in One HTML File

Build a playable Snake game with AI in 30 minutes — one file, no installs — and learn the iteration loop that makes AI coding actually work.

DifficultyBeginner
Time30–45 min
You'll needClaude, ChatGPT, or Gemini (free tier works) · A text editor and a browser
You'll buildA polished, playable Snake game with score, speed-up, game over screen, and mobile touch controls — in a single HTML file you can double-click to play or upload anywhere.

Games are the best first coding project with AI for one reason: you can see every bug. If the snake walks through walls, you don't need to read the code to know something's wrong — you watch it happen, describe it in English, and the AI fixes it. That feedback loop is the whole skill.

Step 1 — The starter prompt

Create a complete Snake game as a single HTML file with all CSS and JavaScript inside it. Requirements: HTML5 canvas, arrow-key controls, food that grows the snake, score counter, game speeds up slightly every 5 points, a start screen and a game-over screen with 'play again'. Visual style: dark background, neon green snake, subtle grid. No external libraries. Output only the code.

Save the output as snake.html and double-click it. You should be playing within two minutes of starting this tutorial.

Step 2 — Play-test like a QA engineer

Now play it with intent to break it. Common first-draft bugs: the snake can reverse into itself and instantly die; food spawns on top of the snake; holding a key queues up moves weirdly; the game-over screen doesn't reset the score. Write down everything that feels wrong.

Step 3 — Report bugs in plain English

Paste your bug list back into the same chat, one batch at a time:

Three bugs to fix: 1) If I press the opposite arrow key, the snake reverses into itself and dies — pressing the reverse direction should be ignored. 2) Food sometimes spawns on the snake's body — it should only spawn on empty cells. 3) After game over, the score doesn't reset. Give me the full corrected file.

Worth knowingAlways ask for 'the full corrected file', not a patch. Beginners lose hours trying to splice AI-suggested snippets into the right place. Full file every time — it's free.

Step 4 — Add a feature the AI didn't think of

This is where it becomes your game. Pick one: touch/swipe controls so it works on phones, a local high score that persists, golden bonus food worth 5 points that disappears after 4 seconds, or sound effects. Describe it precisely and ask for the full updated file.

Step 5 — Ship it

Rename it index.html, upload it to any web host (see the first-website tutorial for the 5-minute version), and you have a game on the internet. A folder per game — yoursite.com/snake/, yoursite.com/breakout/ — and you've got the beginnings of a games site.

Why this works

You just ran the professional loop: spec → build → test → bug report → fix → feature → ship. The vocabulary was English the whole time. When people say '63% of vibe coders aren't developers', this loop is what those people are actually doing.

Keep going

Need somewhere to put it live? See where to host AI-built sites. Compare tool costs on the pricing tracker (or stick to the free options), then pick your next build.