How to Build a Chrome Extension Without Writing Code with AI Tools

A Chrome extension is a small add-on that changes how Chrome or a website works. AI tools can now write the code for you while you describe what you want.

• A button that summarizes the page
• A word counter or reading timer
• A tab or bookmark organizer
• A focus timer that blocks distracting sites
• A tool that highlights keywords on pages

You bring the idea and the testing. AI writes the code.

• Solves one problem you have every day
• Works on your own computer first
• Needs few permissions
• Does not collect personal data

Claude or ChatGPT

Chat-based: they write the files and you copy them into a folder

Claude Code or Codex

Agent-based: they create the files in a folder for you and fix errors themselves

Cursor or Grok Build

Other coding agents that work the same way

Agent-based tools are easiest for beginners because you do not copy files by hand.

Build a Chrome extension using Manifest V3. What it does: [one sentence]. How it works: when I click the toolbar icon, [what happens]. Design: [simple, light colors, font]. Rules: use the fewest permissions possible, no external servers, no tracking, and store settings only in Chrome storage. Give me every file and step-by-step instructions to load it in Chrome.

manifest.json

The extension’s name, version, and permissions. It must use Manifest V3.

popup.html

The small window that opens from the toolbar

Scripts

The code that does the work

Icons

Images for the toolbar and store

You do not need to write these. It helps to know what they are when the AI mentions them.

• Put all the files in one folder
• Open chrome://extensions
• Turn on Developer mode
• Click Load unpacked and choose the folder
• Pin the extension and try it

• Try every button and setting
• Test it on several websites
• Copy any error from chrome://extensions back to the AI
• Ask for one change at a time
• Click reload on the extension after each change

Here is the error and what I expected to happen. Fix only this problem and tell me which files changed.

• Ask the AI why each permission is needed
• Avoid access to all websites unless the extension truly needs it
• Fewer permissions mean more trust and a faster store review

• Do not collect browsing history or personal data unless the extension needs it
• Never put API keys or passwords in the extension code, because anyone can read it
• Ask the AI to check the code for tracking or data sharing

• Register as a Chrome Web Store developer, which costs a one-time $5 fee
• Zip the folder
• Add a description, screenshots, and icons
• Explain each permission and how you handle data
• Add a privacy policy if you handle any user data
• Submit for review

Extensions must follow Chrome Web Store policies, including having a single, clear purpose. Check the current rules before submitting.

• Starting with a big, complex idea
• Accepting every permission the AI suggests
• Not testing on different websites
• Copying other extensions’ code or branding