GUIDES · BETSLIP DOCTOR
How do NBA rebounds, rebound chances and adjusted rebound percentages fit together?
A rebound is a recovery after a missed shot. A rebound chance is a separate tracking opportunity based on being closest to the ball during a defined window. REB Chance% divides rebounds by chances; Adjusted REB Chance% removes deferred chances from that denominator. REB% instead describes available rebounds grabbed while on the floor.
For NBA fans trying to understand player-tracking and box-score terms. · Updated
A rebound is a recovery; a chance is an opportunity
The NBA Stats Glossary defines a rebound as a player recovering the ball after a missed shot. It defines a rebound chance by position relative to the ball: a player has a chance if they are the closest player at any point after the ball crosses below the rim and before it is fully rebounded.
That means the two terms answer different questions. REB describes a recovery that happened. REB Chances describe the tracking opportunity window, whether or not that player ultimately gathers the ball.
- REB: the player or team collected the ball after a miss.
- REB Chance: the player met the glossary's closest-to-the-ball condition during the stated window.
Read each percentage by its stated denominator
The glossary publishes REB Chance% as REB divided by REB Chances. Adjusted REB Chance% uses REB divided by REB Chances minus Deferred REB Chances. A deferred chance is one the player has but defers to a teammate.
REB% has a different definition: the percentage of available rebounds a player or team grabbed while on the floor. Its glossary entry provides that definition but does not display a formula. This guide does not infer an additional equation or treat REB% and REB Chance% as interchangeable.
- REB Chance% uses rebound chances.
- Adjusted REB Chance% removes deferred chances from the chance denominator.
- REB% refers to available rebounds while the player or team is on the floor.
Keep offensive and defensive opportunities separate
The glossary defines offensive rebounds and offensive rebound chances separately from defensive rebounds and defensive rebound chances. It uses the same closest-player opportunity concept in the corresponding offensive or defensive context.
A single sample can include both kinds of chances. The labels describe which side of the play the tracking category refers to; they do not predict who will secure a later rebound.
A fictional rebound ledger
In a made-up stretch, Player A is on the floor while 10 rebounds are available. The ledger records 4 rebounds for A: 2 offensive and 2 defensive. It also records 8 chances for A: 3 offensive and 5 defensive. During one of those eight chances, A is closest to the ball but defers to a teammate, so the ledger records 1 deferred chance. The teammate's recovery is not added to A's REB count. Using the glossary equations, A's REB Chance% ratio is 4 divided by 8, or 0.5 (50%). The Adjusted REB Chance% ratio is 4 divided by (8 minus 1), or 4/7; any displayed rounding is not specified by the glossary. For REB%, the ledger includes 10 available rebounds while A is on the floor, but the glossary entry does not show an equation, so this example does not assign an official REB% value. Separate zero-denominator check: in another fictional interval, a player has 0 REB and 0 REB Chances. The REB Chance% equation would divide by zero. The glossary does not state how a product displays that case, so the example reports no percentage instead of inventing zero, blank, or another value.
Related questions
Does every rebound chance become a rebound for that player?
No. The glossary defines a chance using the player's position relative to the ball during the opportunity window; a rebound is the player's recovery after a miss. A chance and a recovery are different records.
Can I calculate REB% from the glossary entry alone?
The entry defines REB% as the percentage of available rebounds a player or team grabbed while on the floor, but it does not show a formula there. Do not supply an extra equation or assume it is the same as REB Chance%.