To try the thousands of add-ons available here, download Mozilla Firefox, a fast, free way to surf the Web!


Welcome to Firefox Add-ons.

Choose from thousands of extra features and styles to make Firefox your own.


On the go?

Check out our Mobile Add-ons site.


Add-on SDK: Create Add-ons Quickly and Easily

The Add-on SDK provides powerful APIs that allow developers to create add-ons for Firefox using HTML, CSS and JavaScript. When your add-on is complete, we make it easy to share it with over 400 million Firefox users world wide.

Add-on SDK

The Add-on SDK is set of APIs bundled with a command line utility that allows you to develop add-ons with your own tool chain.

  • Choose your own code editor
  • Access your development files locally
  • Get greater control over SDK build steps
Download the Add-on SDK

Help is at Hand!

Need some support building your add-on? We have extensive documentation and a massive developer community to make sure you're never on your own.