MyLoLMMR is a popular third-party tool that allows League of Legends players to check their Matchmaking Rating (MMR) outside of the game. By inputting a summoner’s name, MyLoLMMR provides an estimate of the player’s current MMR, giving insights into their skill level and rank. This tool helps players track their progress, analyze performance trends, and understand how their MMR correlates with their visible rank, making it easier to strategize and improve in ranked matches.