Bundle Scanner is a free Chrome extension developed by markus.s.englund. It falls under the Browsers category, specifically the Add-ons & Tools subcategory.

With Bundle Scanner, you can easily identify which npm libraries are used on any website you visit. The extension thoroughly analyzes every Javascript file from the website you're currently visiting, searching for code that matches any of the 101,962 releases it has indexed from 35,003 of the most popular npm libraries on the web.

While the results provided by Bundle Scanner are not 100% accurate, it offers valuable insights. In benchmark tests, it was found that approximately 15% of libraries that are actually present in the bundle are not identified, and around 5% of the identified libraries are false positives. Despite these limitations, Bundle Scanner remains a useful tool for developers and users who want to understand the npm libraries utilized by a website.