Every metric on the site, explained in plain language.
GPI (Game Performance Index)
Our proprietary composite rating system that combines multiple advanced metrics, opponent-adjusted stats, and external rating systems to provide a holistic team evaluation.
ELO Rating
A rating system borrowed from chess that adjusts team ratings based on game results and margin of victory. Winning against stronger opponents increases your rating more than beating weaker teams.
SRS (Simple Rating System)
A rating that considers both average point differential and strength of schedule. It represents how many points better/worse a team is than average.
SP+ (Success Rate Plus)
ESPN's advanced metric that measures efficiency and explosiveness on a per-play basis, adjusted for opponent strength.
FPI (Football Power Index)
ESPN's predictive rating that uses team efficiency, special teams, and recent performance to project future success.
PPA (Predicted Points Added)
Measures the expected points added (or lost) on each play based on down, distance, and field position. Averages all plays to show offensive/defensive efficiency.
Success Rate
Percentage of plays that are "successful" - 50%+ of needed yards on 1st down, 70%+ on 2nd down, or 100%+ on 3rd/4th down.
Explosiveness
Measures the magnitude of successful plays. The average Expected Points Added (EPA) on successful plays only.