About: Performance rating (chess)

Performance rating (abbreviated as Rp) in chess is the level a player performed at in a tournament or match based on the number of games played, their total score in those games, and the Elo ratings of their opponents. It is the Elo rating a player would have if their actual score was the expected score they would get against their opponents based on their opponent's individual ratings. Due to the difficulty of computing performance rating in this manner, however, the linear method and FIDE method for calculating performance rating are in much more widespread use. With these simpler methods, only the average rating (abbreviated as Rc) factors into the calculation instead of the ratings of each individual opponent. Regardless of the method, only the total score is used to determine performa