PER Calculator (Player Efficiency Rating)

PER is a per-minute performance rating developed by ESPN columnist John Hollinger. It sums up all of a player's positive statistical contributions, subtracts the negative ones, and normalizes the result per minute of play. The league average PER is always set to 15.0.

This calculator uses a simplified PER formula: PER = (Positive Contributions − Negative Contributions) / Minutes × 15. Positive contributions include points, weighted rebounds, assists, steals, blocks, and shot-making bonuses. Negative contributions include turnovers, missed field goals, and missed free throws.

The league average PER is 15.0. A PER above 20 is considered excellent and indicates an All-Star caliber player. A PER above 25 is MVP-level, while scores above 30 are historically rare and represent the greatest individual seasons ever recorded. Anything below 10 is generally below average.

Michael Jordan holds the highest career PER in NBA history at approximately 27.91. Other all-time leaders include LeBron James, Shaquille O'Neal, David Robinson, and Wilt Chamberlain, all of whom posted career PERs above 24.

PER is heavily weighted toward offensive production and does not fully capture defensive value. It also doesn't account for pace, team context, or opponent quality. A player on a faster-paced team may accumulate more opportunities, inflating their PER. It's best used as one tool among many rather than the sole measure of player value.

PER was designed to be era-adjusted since it is normalized to a league average of 15.0 each season. This makes cross-era comparisons more meaningful than raw stats. However, rule changes, pace shifts, and overall league talent level still make direct comparisons imperfect.

The full Hollinger PER formula requires league-wide statistics (league average assists, field goals, free throws, pace, etc.) that change every season. The simplified formula used here produces a close approximation based solely on individual player stats, making it accessible without needing external league data.

EFF (Basketball Efficiency) is a simpler metric: EFF = (PTS + REB + AST + STL + BLK − Missed FGs − Missed FTs − TOV) / Games Played. PER is more sophisticated, weighting each stat differently and normalizing per minute of play. PER is generally considered a more nuanced evaluation tool than EFF.