Sports & Gaming · Statistics · Descriptive Statistics
Player Efficiency Rating (PER) Calculator
Calculate a basketball player's Player Efficiency Rating (PER) using John Hollinger's formula based on per-minute statistical production.
Calculator
Formula
uPER is the unadjusted PER per minute. MP=minutes played, 3P=three-pointers, AST=assists, FG=field goals made, FT=free throws made, FTA=free throw attempts, TRB=total rebounds, ORB=offensive rebounds, STL=steals, BLK=blocks, TO=turnovers, PF=personal fouls. League/team factors (VOP, DRB%, tmAST/tmFG, lgFT/lgPF, lgFTA/lgPF) adjust for pace and context. The simplified calculator uses a well-known approximation scaled so the league average PER is 15.
Source: John Hollinger, 'Pro Basketball Forecast' 2002–03; ESPN PER methodology.
How it works
PER starts by computing an unadjusted per-minute score (uPER) that credits positive contributions — field goals, free throws, three-pointers, rebounds, assists, steals, and blocks — and penalizes negative ones like missed shots, missed free throws, and turnovers. Each statistical category carries a coefficient derived from its estimated value relative to a possession. For example, a made field goal is worth more than an assist, and a turnover is a heavy negative because it surrenders an entire possession.
The raw uPER is then multiplied by a pace-adjustment factor derived from league-wide and team-level data, and finally scaled so that the league average equals exactly 15.0. This normalization means a PER of 15 is league-average regardless of the season or pace era. This calculator uses an approximation of Hollinger's formula that closely tracks official PER values based on per-game averages, making it ideal for comparing players from publicly available box scores.
PER is widely used in NBA front offices, sports media, and fantasy basketball to quickly benchmark players. It is especially useful when comparing players with different minutes distributions, since the per-minute structure rewards efficiency over raw volume.
Worked example
Example: LeBron James-type season line
Suppose a player averages over 70 games: 27 pts, 7.5 reb, 7.3 ast, 1.7 stl, 0.9 blk, 3.0 to on 10.0 FGM / 19.5 FGA, 6.5 FTM / 8.5 FTA, 2.1 3PM in 37.5 minutes.
Step 1 — Per-36 adjustment: scale all stats to a 36-minute baseline (e.g., pts_36 = 27 × 36/37.5 = 25.9).
Step 2 — Weighted sum: combine each stat with its Hollinger coefficient. Positive items: pts + 0.4×FGM − 0.7×FGA − 0.4×(FTA−FTM) + 0.7×reb + 0.3×ast + stl + 0.7×blk. Negative items: subtract turnovers.
Step 3 — Scale uPER to league average = 15.0. With typical league constants, this player scores approximately PER ≈ 27–30, placing them in the All-Star / All-NBA tier.
Note: The exact official PER requires season-level team and league constants (pace, VOP, DRB%) published by Basketball-Reference after each season.
Limitations & notes
PER has several well-documented limitations. First, it does not fully capture defense — steals and blocks are included, but defensive positioning, help-side coverage, and on/off defensive ratings are not. Second, PER rewards high-volume scorers even when their efficiency is below average if they accumulate enough counting stats. Third, the formula is optimized for traditional positions; it tends to overvalue high-usage bigs and undervalue three-and-D wings who contribute through spacing rather than box-score statistics. Fourth, since this calculator uses a simplified approximation, results may differ from the official Basketball-Reference PER by 0.5–2.0 points, because official calculations require season-level team and league constants (VOP, pace factor, DRB%) that change each year. Finally, very small samples (fewer than 10 games or 100 minutes) produce unstable PER values that should not be used for meaningful comparison.
Frequently asked questions
What is a good PER in the NBA?
The league average PER is calibrated to 15.0. A PER above 20 indicates an All-Star-level player, while a PER above 25 marks a superstar or MVP candidate. Historical greats like Michael Jordan, LeBron James, and Nikola Jokic have career PERs above 27. A PER between 10 and 15 is typical for rotation players, while below 10 suggests a below-average contributor.
Why does this calculator produce slightly different results than Basketball-Reference?
Official PER requires real-time season constants: team assist-to-field-goal ratio (tmAST/tmFG), league value of a possession (VOP), league defensive rebound percentage (DRB%), and personal foul weighting based on league free throw rates. These factors change every season. This calculator uses a well-established approximation that closely tracks official PER but may differ by 0.5–2.0 PER points without the exact season constants.
Does PER measure defense?
PER only partially captures defense. It includes steals and blocks as positive contributions, but it does not account for defensive positioning, pick-and-roll coverage, help rotations, or contest quality. For a more complete defensive picture, analysts supplement PER with Defensive Rating, Defensive Win Shares, or Defensive Box Plus/Minus (DBPM).
Who invented PER and when?
PER was invented by John Hollinger, a basketball analyst who later became Vice President of Basketball Operations for the Memphis Grizzlies. He first published the formula in his book 'Pro Basketball Forecast' for the 2002–03 season and later popularized it as a columnist at ESPN. It became one of the first widely adopted advanced basketball statistics.
Can I use PER for college basketball or international leagues?
PER can be adapted for any basketball league, but the scaling constants must be re-derived for each league's pace and team tendencies. Using NBA league constants for FIBA, EuroLeague, or NCAA data will produce numbers that are not comparable to the NBA 15.0 baseline. Analysts often compute an unscaled version for cross-league comparisons and then normalize within each league separately.
What is the highest PER ever recorded in NBA history?
Wilt Chamberlain holds the all-time single-season PER record at approximately 31.8 during the 1962–63 season. Among modern players, Giannis Antetokounmpo, LeBron James, and Nikola Jokic have reached single-season PERs above 30. The threshold of 30+ PER is considered generationally elite and has been achieved fewer than 20 times in NBA history.
Should I enter per-game averages or season totals?
This calculator accepts per-game averages combined with games played, which it multiplies internally to compute season totals before normalizing by total minutes. Enter your per-game averages (e.g., 22.5 points per game) along with minutes per game and total games played. Do not enter raw season totals — this will overcount statistics and produce inflated PER values.
Last updated: 2025-01-30 · Formula verified against primary sources.