What is the difference between the RPI rankings and the Top 25 rankings? August 28, 2018 23:29 Updated The RPI (rating percentage index) is a standardized formula based on winning percentages, and the Top 25 rankings are a simulated media poll. More information about RPI can be found here. More information about the Top 25 rankings can be found here. Related articles What does "home court advantage" mean? Does it change? How are the Top 25 rankings determined? What is the RPI? Are there prizes? What are they? Can an Academic Ineligible player take a red-shirt?