The Rating Percentage Index is primarily used in collegiate sports to rank teams based on win totals and strength of schedule. Some sports, such as college basketball, also take a team's RPI into account when selecting teams that enter the sport's postseason.
A team's RPI is calculated using the team's winning percentage, the total winning percentage of the team's opponents and the total winning percentage of the opponents' opponents. The RPIs of college basketball and baseball use a slightly adjusted formula where home and road wins are weighted differently. While the RPI is only one factor used by the NCAA Selection Committee in college basketball, teams with the top 25 RPI scores are usually selected to enter the postseason.