What Is Player Efficiency Rating (PER) in Basketball?

Player efficiency rating (PER) is a single number that sums up everything a player does on the court — scoring, rebounding, assists, steals, blocks, and the negatives like missed shots and turnovers — into one per-minute, pace-adjusted rating. Created by analyst John Hollinger, its defining feature is the scale: PER is rescaled every season so that the league average is always exactly 15.00. That fixed anchor is the whole point. A 22 PER means the same thing this year as it did twenty years ago, because average is pinned at 15 no matter how the game’s scoring environment shifts.

How PER is built (in plain terms)

The full PER formula is genuinely long — it credits a player for every positive box-score event, subtracts for the negatives, adjusts for team pace so fast and slow teams are compared fairly, converts everything to a per-minute basis, and then rescales the league to a 15.00 average. Reproducing all twenty-plus terms by hand is not the goal, and trying to would only invite mistakes.

What matters is the logic in three steps:

• Add up the good, subtract the bad. Points, rebounds, assists, steals, and blocks push PER up; missed field goals, missed free throws, and turnovers pull it down, each weighted by an estimate of its value.
• Make it per-minute and pace-neutral. A player who produces the same in fewer minutes rates higher, and playing on a fast team does not inflate the number.
• Anchor the league at 15. The final rescaling guarantees average is always 15.00, which is what makes cross-era comparison possible.

How to read PER

Because 15 is fixed as average, the tiers are easy to hold onto.

PER	Rating
30.0 and up	Historic, all-time season
25.0 to 29.9	MVP-level
22.9 to 24.9	All-Star
20.0 to 22.8	Borderline All-Star
16.5 to 19.9	Solid starter
15.0	Exactly league average
Below 13	Bench-level or worse

The highest single-season PERs in history have reached into the low 30s — a level so far above 15 that it captures the most dominant statistical years the sport has produced.

The catch: what PER gets wrong

PER’s convenience is also its weakness, and it is worth being blunt about it. The formula is built almost entirely from the box score, which creates two well-known distortions:

• It rewards volume. A player who takes a lot of shots can pad PER even at mediocre efficiency, because makes add more than misses subtract in the weighting. Hollinger himself acknowledged PER is not a pure efficiency stat despite the name.
• It undervalues defense. Steals and blocks are the only defensive events in the box score, so an elite perimeter defender who alters shots and never gambles for steals gets almost no credit. Great defense that does not show up in the numbers is largely invisible to PER.

Because of that, PER is best treated as a fast summary rather than a final ranking. It tells you who is producing a lot per minute; it does not settle who is the most valuable player, especially on the defensive end.

Where PER fits with other stats

For the specific things PER blends together, the single-purpose stats are sharper. True shooting percentage isolates scoring efficiency, effective field goal percentage isolates shot-making, and usage rate isolates how much of the offense a player carries. Read together, they give the detail PER compresses into one figure.

To see the players whose all-around production drives PER to its heights, the greatest NBA players is stacked with the names atop the career leaderboard, and the highest-scoring NBA game shows what peak box-score output looks like on the scoreboard.

In short: PER is Hollinger’s per-minute, pace-adjusted summary of box-score value, scaled so 15 is always average and 25-plus is MVP-level — a handy shorthand that leans toward scorers and shortchanges defenders, so use it alongside sharper stats, not instead of them.