Batting average, OBP, SLG and OPS calculator
Enter a hitter’s numbers and the calculator works out batting average, on-base percentage, slugging and OPS with the same formulas the major leagues use. Nothing is saved or sent.
- AVG
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- OBP
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- SLG
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- OPS
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Batting average (AVG)
Batting average is the share of official at-bats that ended in a hit: hits divided by at-bats. A hitter with 45 hits in 150 at-bats is batting .300.
Walks, hit-by-pitches, sacrifice bunts, sacrifice flies and catcher’s interference are not at-bats. That is why a hitter can come to the plate five times in a game and have only three official at-bats.
It is written with three decimals and no leading zero: .300, not 0.300. A 1.000 average keeps its one.
On-base percentage (OBP)
OBP measures how often a hitter reaches base on his own: hits plus walks plus hit-by-pitches, divided by at-bats plus walks plus hit-by-pitches plus sacrifice flies.
A sacrifice fly counts in the denominator even though it is not an at-bat, because the hitter had a chance to reach base and did not. A sacrifice bunt does not count. Reaching on an error or a fielder’s choice does not count either: it is not the hitter’s doing.
Slugging (SLG)
Slugging weighs each hit by the bases it earned: total bases divided by at-bats. A single is worth one base, a double two, a triple three and a home run four.
With 2 hits in 4 at-bats, one of them a double and the other a home run, total bases are 6 and slugging is 1.500. That is why the calculator asks for total hits and, separately, doubles, triples and home runs: extra-base hits are part of the hits, never more than them.
OPS
OPS is on-base percentage plus slugging. It puts how often a hitter gets on and how hard he hits into one number, which is why it is the most common way to compare hitters at a glance.
As a professional reference, an OPS of .800 is good and .900 is excellent. In an amateur league the numbers swing with the level of pitching, so compare each hitter with the others in his own league.
In your league, without a calculator
On RosterMetrix each manager loads their team’s sheet after the game and the commissioner approves it. From then on every player’s average, OBP, slugging and OPS work themselves out, with the leaderboard, the minimum at-bats to qualify and each player’s page up to date.
On RosterMetrix each manager loads their team’s sheet, the commissioner approves the game, and averages, ERA, the leaders and every player’s page update on their own.