atbat

At bat, abbreviated AB, is a baseball statistic that credits a batter for every completed plate appearance that does not end with a walk, hit by pitch, intentional walk, sacrifice bunt, the sacrifice fly, or catcher’s interference. In practical terms, an at bat occurs when a batter either makes an out or reaches base by a hit or other legal means not excluded above. AB is the statistic most closely associated with batting average, since batting average is calculated as hits divided by AB.

At bats are counted as part of a batter’s plate appearance, but they are not the same as plate appearances (PA). A PA includes all outcomes from a batter’s turn at the plate: walks, hit by pitch, intentional walks, sacrifices, and catcher’s interference are included in PA but do not count as AB. For example, if a batter walks, his PA increases but his AB does not. If a batter hits a single or is retired via an out, that counts as an AB.

Common uses and implications: AB is a key component of batting average (hits/AB) and is used in other calculations that need a denominator for batting performance, such as slugging percentage (total bases/AB). Because AB excludes walks, hit by pitch, and sacrifices, it provides a focused view of a batter’s actions when confronted with a pitch, either resulting in an out or a hit.

Edge cases and notes: Sacrifices (bunts or flies) do not count as AB. Catcher’s interference is also excluded from AB. The definition of an at bat can be nuanced in rare scoring situations, but the general rule is that AB covers plate appearances that end with either an out or a hit, excluding the listed exceptions.