The Holy Grail of Box Scores
Created by ESPN analyst John Hollinger, the Player Efficiency Rating (PER) was the first major breakthrough in advanced basketball analytics. It attempts to distill all of a player's positive accomplishments (points, rebounds, assists, steals, blocks) and negative outcomes (missed shots, turnovers) into a single, comprehensive number.
By standardizing this number across the entire league, analysts finally had a way to compare the overarching impact of a point guard directly against a center.
The Linear Estimation
The true NBA PER formula is incredibly complex. It requires adjusting for the team's precise pace of play and standardizing the entire league so the average PER is exactly 15.00.
Because pace data isn't available for recreational or amateur games, this calculator uses the highly accurate Linear Game Score Approximation—a foundational piece of the PER puzzle that functions beautifully as an unadjusted, standalone efficiency metric.
The Formula
The approximation takes a simple sum of all positive box score statistics and subtracts the negative penalties.
Game Score = (PTS + REB + AST + STL + BLK) - (FGA - FGM) - (FTA - FTM) - TO
Interpreting the Score
- 30.0+ : A legendary, MVP-caliber performance.
- 20.0 to 25.0 : An All-Star level performance.
- 15.0 : A perfectly average performance.
- Below 10.0 : A highly inefficient, detrimental performance.