What Is Player Efficiency Rating? How to Read PER

Player Efficiency Rating (PER) is a basketball statistic that summarizes a player’s box-score production per minute, adjusts for team pace, and sets the league average to 15 each season. John Hollinger developed it to combine scoring, passing, rebounding and other recorded contributions into one number. Higher is better within the metric—but PER is not a complete measure of how much a player helps a team win. Hollinger’s explanation makes that distinction explicit.

The key is to read PER as a rate of statistical production, not a shooting percentage, a season total or a definitive player ranking.

What goes into PER?

PER gives weighted credit for made field goals, made free throws, three-pointers, assists, rebounds, steals and blocks. It subtracts value for missed shots, turnovers and personal fouls. Those events receive different weights; an assist and a rebound are not simply interchangeable additions. Hollinger outlines the inputs here.

The calculation then makes three important adjustments:

1. Minutes: It divides the weighted production by minutes played. A reserve can therefore have a higher PER than a starter despite producing smaller season totals.
2. Pace: It adjusts for the team’s pace relative to the league. Faster teams generate more possessions—and more opportunities to accumulate statistics—in the same playing time.
3. League baseline: It scales the result so the league’s minutes-weighted average is exactly 15 each season.

Basketball-Reference’s calculation guide provides the full formula. Its final steps can be written more simply as:

Pace-adjusted production = unadjusted per-minute production × (league pace ÷ team pace)

PER = pace-adjusted production × (15 ÷ league-average pace-adjusted production)

The league average in that last step is minutes-weighted. PER is neither a raw per-minute statistic nor a direct count of points produced per possession.

What is a good PER?

For NBA interpretation, 15 is the fixed reference point. The descriptions below are practical shorthand, not official award or roster thresholds.

PER	How to read it
10	Below-average box-score production per minute
15	League-average box-score production per minute
20	Clearly above average
25	Very high production
30	Exceptional production

The average is minutes-weighted, not the median player’s rating or the simple average of every rostered player. Players who log more minutes carry more weight in establishing the baseline. Basketball-Reference explains that normalization.

For a concrete example, ESPN’s 2021–22 NBA regular-season center table lists Nikola Jokić at 32.94 PER in 33.5 minutes per game and JaVale McGee at 22.65 PER in 15.8 minutes per game. Both ratings are well above 15, but the minutes show very different workloads. McGee’s rating describes strong production in limited minutes; it does not establish that he could sustain it over Jokić’s workload. Source: ESPN’s 2021–22 table.

A PER of 20 also does not mean 20 points per game—or that a player is 33% better overall than someone at 15.

What PER misses

Defense beyond steals and blocks. Containing a ball handler, rotating correctly or discouraging a shot may leave no positive entry in the traditional box score. Hollinger specifically warns that PER can miss the value of defensive specialists who record few steals or blocks. His explanation treats PER as a starting point, not a final evaluation.

Role and opportunity. Pace adjustment does not make every assignment equally difficult. Shot creation, off-ball spacing and matchup responsibilities still need separate evaluation. Check workload with usage rate; use effective field-goal percentage when the question is specifically about shooting efficiency.

Total season contribution. PER is a rate statistic. Read it alongside games and total minutes rather than treating a short, productive stretch as equivalent to a full season.

Perfect cross-era comparability. Setting every season’s average to 15 helps compare production relative to contemporaries, but it does not erase changes in rules, roles or recorded data. Basketball-Reference’s historical calculations omit or estimate inputs where statistics are missing, including steals and blocks before 1973–74 and player turnovers before 1977–78. It also estimates pace adjustments before 1973–74. Its methodology documents those limits.

Use PER to ask, “How productive was this player’s recorded box-score activity per minute, after pace adjustment?” For broader questions about impact, pair it with other evidence, such as Box Plus-Minus, lineup results and observation of what happens beyond the box score.