Stats Glossary

Basketball is a game of opportunities, and to measure those opportunities properly, you need precise language. Two terms sit at the foundation of almost every advanced metric in basketball: possessions and plays. They are related but not interchangeable, and the difference between them matters more than most people realize. What follows are the definitions used consistently across all statistics.

Definition: Basketball Possession

A possession is the full sequence of events belonging to one team — from the moment they gain control of the ball to the moment the opposing team gains control. A possession can contain multiple scoring attempts; it only ends when the ball changes hands.

  • • [Team A] Non-shooting foul drawn
  • • [Team B] Foul committed
  • • [Team A] Missed 3FG
  • • [Team A] Offensive rebound
  • • [Team A] Missed 2FG
  • • [Team B] Defensive rebound ← possession ends

Everything above is 1 possession. Team B never had control of the ball until that final defensive rebound. The key takeaway: a single possession can contain multiple failed scoring attempts before it's over.

Definition: Basketball play

A play is a single scoring opportunity within a possession. It begins when a team gains (or retains) control of the ball and ends either when a shot goes up or when the opposing team gains control. Because of this, a possession always consists of at least one play, and offensive rebounds are what create additional plays within the same possession.

First play
[Team A] Non-shooting foul drawn [Team B] Foul committed

Team A has the ball, Team B commits a non-shooting foul, Team A retains possession and the play ends there.

Second play
[Team A] Missed 3FG [Team A] Offensive rebound

Team A shoots the ball, the play ends the moment it goes up. Grabbing the offensive rebound starts a new play while the possession continues.

Third play
[Team A] Missed 2FG [Team B] Defensive rebound

Another attempt from Team A, but this time the opposing team gains control, ending both the play and the possession simultaneously.

Offensive Rating (ORTG)

Points scored (by a team) or produced (by an individual) per 100 possessions.

ORTG = 100 × (points scored)/(possessions)

Defensive Rating (DRTG)

Points allowed (by a team or individual) per 100 possessions.

DRTG = 100 × (points allowed)/(possessions)

Net Rating (NETRTG)

Difference between the offensive and defensive rating, shows how many more or fewer points a team produces relative to what they allow.

NETRTG = ORTG - DRTG

Why ORTG, DRTG and NETRTG are important?

The most natural way to evaluate a team's offense or defense is by looking at points scored or allowed — whether that's points per game, points per shot, or field goal percentage. These are all useful, but each is missing something:

  • Points per game get higher for teams that played overtime, and ignore pace entirely, a fast team will naturally score more just by having more possessions.
  • Points per shot and field goal percentage only capture shooting quality. They miss the team that compensates for poor shooting with offensive rebounds, or the team that protects the ball exceptionally well with less turnovers.

Offensive and defensive rating cut through these limitations by asking one straightforward question: how many points does a team score per possession? It doesn't matter how they get there, efficient shooting, drawing fouls, second-chance points. All that counts is whether the ball ends up in the basket.

Metrics Explained

PPG (Points per game)
PPG = PTS / Games Played

The player's average points per game.

eFG% (Effective FG%)
100 × (FGM + 0.5 × 3PM) / FGA

Adjusts FG% to account for 3-pointers counting 50% more than 2-pointers.

TS% (True shooting)
100 × Points / (2 × (FGA + 0.44 × FTA)

Measures shooting efficiency including possession ending free throws.

AST% (Assist rate)

Percentage of teammate FGs assisted by player while on the floor.

pAST (Points assisted)

Number of points produced by the assists of a certain player.

USG% (Usage rate)

Percentage of team offensive possessions used while on floor.

TOV% (Turnover percentage)
100 × TOV / Possessions

Player's turnovers per 100 individual plays.

ORB% / DRB%
ORB% = 100 × ORB / (ORB + Opponent DRB) DRB% = 100 × DRB / (DRB + Opponent ORB)

Percentage of available offensive/defensive rebounds grabbed while on floor.

Free Throw Rate
FT Rate = 100 × FTM / FGA

Free throw rate measures a team/player's ability to get to the free throw line, and turns it into points.

Pace

Possessions per 48 (NBA) or 40 (FIBA/Euro) minutes.