Google Cache Checker is an extension for Firefox that allows users to quickly determine if a webpage is included in Google's search index. This tool is beneficial for tracking the indexing status of your own website or other pages of interest. By adding a small icon to Firefox's status bar, it provides instant visual feedback - green for indexed and red for not indexed. Moreover, users can access the cached version of indexed pages and view the date it was cached.

This extension simplifies the process of checking Google's index status, offering a convenient solution for website owners and content creators to monitor their online presence effectively.