Opponent On-Base Percentage OOBP

OOBP stands for opponent on-base percentage in baseball. How often opposing hitters reached base against a pitcher — the on-base percentage he allowed.

How OOBP is calculated

OOBP = (H + BB + HBP) ÷ (AB + BB + HBP + SF), counted against him

Walks move it and batting average against does not see them, so two pitchers with the same average against can sit 40 points apart here. The median pitcher with 100 innings allowed .310 in 2025.

What counts as a good OOBP?

Half of the 324 qualified MLB players in 2026 were at or below .311. The best tenth were under .268.

Median: .311
Top 10% (low): .268
Leader: .217

By position, the median was .308 for RP and .315 for SP.

Qualified: 50+ IP, non-zero, 2026 regular season.