Build Your Own Browser Extension

Learn to create extensions that users can trust

Our Philosophy

This guide will teach you how to build extensions the right way - with transparency, respect for user privacy, and ethical practices. We've seen too many extensions abuse user trust. Let's build better tools together.

Getting Started
Basic concepts and your first extension

What You'll Learn:

  • Extension architecture and file structure
  • Manifest V3 basics (the latest standard)
  • Creating popup UIs with HTML/CSS/JavaScript
  • Loading your extension for development

Resources:

Chrome Extension Getting Started Guide →MDN: Your First Extension →
Core Development Concepts
Master the essential APIs and patterns

Key Topics:

  • Content scripts vs. background scripts
  • Message passing between scripts
  • Storage API for saving user data
  • Permissions and why to minimize them
  • Working with browser tabs and windows

Best Practices:

  • Request only the permissions you absolutely need
  • Use TypeScript for better code quality
  • Implement proper error handling
  • Test across different websites and browsers
Extension Ethics
Critical: What NOT to do

Never Do These Things:

  • Don't hijack affiliate links - This is what Honey did, and it's unethical. Don't steal commissions from content creators.
  • Don't collect data without clear disclosure - Be transparent about what data you collect and why.
  • Don't inject ads or modify page content unexpectedly - Users installed your extension for a specific purpose.
  • Don't sell user data - Ever. Your users' trust is worth more than money.
  • Don't request unnecessary permissions - Only ask for what you need to function.

Do These Instead:

  • Be transparent about your business model
  • Make your extension open source when possible
  • Provide a clear privacy policy
  • Respect user privacy by default
  • Give users control over their data
Security & Privacy
Build secure extensions users can trust

Security Checklist:

  • Validate and sanitize all user inputs
  • Use Content Security Policy (CSP)
  • Avoid eval() and inline scripts
  • Keep dependencies up to date
  • Don't store sensitive data in localStorage
  • Use HTTPS for all API calls

Privacy Guidelines:

  • Minimize data collection - collect only what's necessary
  • Store data locally when possible (not on your servers)
  • Provide easy data export and deletion
  • Be transparent in your privacy policy
  • Don't track users across websites unless essential
Publishing & Distribution
Share your extension with the world

Steps to Publish:

  1. Create a developer account ($5 one-time fee for Chrome)
  2. Prepare store listing (name, description, screenshots)
  3. Write a clear privacy policy
  4. Package your extension as a ZIP file
  5. Submit for review
  6. Wait for approval (usually 1-3 days)

Marketing Tips:

  • Create a landing page explaining your extension
  • Make a demo video showing key features
  • Share on Product Hunt, Reddit, and Twitter
  • Be responsive to user feedback and reviews
  • Consider making it open source for trust
Additional Resources
Deep dive into specific topics
Official Chrome Extensions Documentation →Firefox Extension Workshop →Open Source Extension Examples on GitHub →Video Tutorials on YouTube →

Ready to Build Something Amazing?

Remember: The best extensions solve real problems while respecting user privacy and trust. Build something you'd be proud to use yourself.

Browse Extensions for InspirationStart Building Now