Free Tool
On-Base Percentage Calculator
Free OBP calculator for baseball and softball: hits, walks, hit by pitch, at-bats and sacrifice flies.
How it works
On-base percentage is how often a batter reaches base: OBP = (H + BB + HBP) ÷ (AB + BB + HBP + SF). Hits, walks and hit by pitch are in the top; at-bats, walks, hit by pitch and sacrifice flies are in the bottom. 14 hits, 5 walks and 1 hit by pitch in 40 at-bats with 1 sacrifice fly is 20 ÷ 47 = .426.
Frequently Asked Questions
What is the formula for on-base percentage?
(hits + walks + hit by pitch) ÷ (at-bats + walks + hit by pitch + sacrifice flies).
Why is OBP higher than batting average?
Batting average ignores walks and hit by pitch. OBP counts every way of reaching base on the batter's own work, so a patient hitter's OBP can be far above their average.
Does reaching on an error count?
No. A batter who reaches on an error, or on a fielder's choice, is not credited with a hit, walk or hit by pitch, so it does not raise OBP.
Is OBP the same in softball?
Yes. The formula does not change between baseball and softball.
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