NBA Efficiency Rating (EFF)
Adds points, rebounds, assists, steals and blocks, then subtracts missed shots, missed free throws and turnovers for the classic NBA efficiency number.
EFF
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NBA Efficiency Rating (EFF)
The classic EFF formula adds positive box-score events and subtracts negatives: EFF = PTS + REB + AST + STL + BLK − (FGA−FGM) − (FTA−FTM) − TOV. It's the simplest efficiency proxy and the basis for the NBA's official Player Efficiency metric. A more sophisticated alternative is John Hollinger's PER (1995), standardized so the league average is always 15.0. LeBron James carries a career PER around 27+; Nikola Jokic owns the all-time single-season record near 32. Modern advanced metrics include Plus/Minus, RAPM, RPM, BPM and VORP, which try to isolate impact beyond raw box-score totals.
Applications
Quick NBA player evaluation, fantasy basketball (Yahoo and ESPN scoring is essentially EFF-shaped), scouting and college-to-pro projections, and historical comparisons across eras. EFF is volume-friendly — high-usage players are favored — so combine it with per-minute or per-possession metrics for fairer benchmarks.
FAQ
EFF vs PER — which is better? PER accounts for pace and league context; EFF is raw and easier to compute. PER is fairer across seasons; EFF works better for single-game lines.
Does EFF reward chuckers? Yes, partially. A player who scores 30 on 12-of-30 shooting can still post a strong EFF. Use True Shooting % alongside it.
What's a great single-game EFF? Above 30 is excellent, above 40 is elite, and historical 60+ performances (Wilt, Kobe's 81-point game) are once-in-a-generation.
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