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On base percentage
From BR Bullpen
(Redirected from OBP)
On Base Percentage (aka OBP, On Base Average, OBA) is a measure of how often a batter reaches base. It is approximately equal to Times on Base/Plate appearances.
The full formula is OBP = (Hits + Walks + Hit by Pitch) / (At Bats + Walks + Hit by Pitch + Sacrifice Flies). Batters are not credited with reaching base on an error or fielder's choice, and they are not charged with an opportunity if they make a sacrifice bunt.
| All Time Leaders | |||
|---|---|---|---|
| Span | Player | Total | Notes |
| Career | Ted Williams | .482 | |
| Season | Barry Bonds | .609 | 2004 |
