LeetCode Friends Rank Checker is a Chrome extension designed to enhance the competitive coding experience on LeetCode by allowing users to track and compare their friends' performance during contests. This tool introduces a dedicated 'Friends' tab on contest leaderboards, enabling users to easily monitor their friends' live rankings, scores, and submission times alongside global rankings. By simply clicking a star icon next to any username, users can add friends and keep track of their progress in real-time.

The extension efficiently retrieves and displays detailed contest data, including country flags, usernames, ranks, total scores, and individual problem times. It utilizes concurrent batched requests to fetch up to 12,500 rankings in about 100 seconds, and it caches data locally for quick access. A user-friendly popup dashboard provides an overview of saved friends, their profile links, current contest ratings, and last submission dates, making it an invaluable tool for competitive coders looking to engage with their peers.