Gera Tools

Basketball Net Rating Calculator

Calculate a team or lineup's net rating from points data.

Enter points scored and allowed plus possessions to compute Net Rating, Offensive Rating, and Defensive Rating — the core per-100-possession efficiency metrics used in NBA analysis. Runs in your browser. It runs free in your browser on Gera Tools, with nothing uploaded.

Last updated Source: Gera Tools

What is Net Rating in basketball?

Net Rating is the difference between a team's Offensive Rating and Defensive Rating, measured per 100 possessions. A positive number means the team outscores opponents at the same pace, and it is the standard way to compare teams and lineups regardless of how fast they play.

Per-game point totals reward fast-paced teams and mislead comparisons. Net Rating fixes this by measuring scoring and defence per 100 possessions, the language NBA analysts use to rank teams and lineups. This calculator computes Offensive, Defensive, and Net Rating from your scoring and possession data.

How it works

Each rating scales scoring to a common 100-possession baseline:

Offensive Rating = 100 × points scored  / possessions
Defensive Rating = 100 × points allowed / possessions
Net Rating       = Offensive Rating − Defensive Rating

If you do not have an exact possession count, enable the estimator, which uses the standard approximation FGA + 0.44 × FTA − OREB + TOV. The same possession figure is applied to both ends, since the two teams share roughly equal possessions in a game.

Worked example

A team that scores 112 points and allows 104 over 98 possessions has an Offensive Rating of 100 × 112 / 98 ≈ 114.3, a Defensive Rating of 100 × 104 / 98 ≈ 106.1, and a Net Rating of about +8.2 — a strong, contender-level margin. Use season-long totals for reliable figures; a single game’s Net Rating can swing by 30 points or more on variance alone.

When to use Net Rating instead of win-loss record

Win-loss records capture outcomes but are compressed and noisy. A team that wins twelve one-point games and loses two blowouts can look excellent by record while its underlying efficiency margin is thin. Net Rating exposes that gap: if a team’s point differential per 100 possessions is near zero over hundreds of possessions, the winning streak is probably unsustainable.

The metric is equally useful for evaluating specific lineups. A five-man unit that shares 200 possessions in a season will have a Net Rating that tells you far more about that combination than whether it happened to win or lose those stints. Coaches and analysts use exactly this logic to identify their most effective units — even lineups that barely played together can show a clear efficiency signal.

Lineup versus team Net Ratings

Team Net Rating covers the full game — it is the weighted average of all lineup combinations. Individual lineup ratings are typically more extreme because of small sample sizes. A bench unit that posts +20 in 30 possessions may simply have faced weak opposing bench players; the number tells you about that matchup, not a generalised quality level.

For lineups, treat any rating from fewer than 100 shared possessions with caution. For teams, the season-long figure (1000+ possessions per team) is one of the most reliable predictors of playoff performance available.

Common mistakes

  • Mixing pace. If you manually assemble stats from two different sources, confirm the possession counts match the same stretch of play. Combining scoring from one game with possessions from another produces a meaningless rating.
  • Small samples. A lineup that played four possessions can have a Net Rating of +100 or -100 — noise, not signal. More possessions tighten the estimate.
  • Ignoring team context. A unit’s Net Rating partly reflects the opposition it faced. A lineup that only plays when the team is up 20 will have an inflated mark because it faces weaker bench opponents.