The main hitting statistics
- Batting average (AVG) = hits ÷ at-bats
- On-base percentage (OBP) = (hits + walks + hit by pitch) ÷ (at-bats + walks + hit by pitch + sacrifice flies)
- Slugging percentage (SLG) = total bases ÷ at-bats
- OPS = OBP + SLG
- Isolated power (ISO) = SLG − AVG
Total bases count 1 for a single, 2 for a double, 3 for a triple and 4 for a home run.
Worked example
A hitter has 500 at-bats, 150 hits including 30 doubles, 3 triples and 20 home runs, plus 60 walks, 5 hit-by-pitches and 5 sacrifice flies.
- Batting average: 150 ÷ 500 = .300.
- Singles: 150 − 30 − 3 − 20 = 97.
- Total bases: 97 + 2 × 30 + 3 × 3 + 4 × 20 = 246.
- OBP: (150 + 60 + 5) ÷ (500 + 60 + 5 + 5) = .377.
- SLG: 246 ÷ 500 = .492.
- OPS: .377 + .492 = .869, a very good season.
- ISO: .492 − .300 = .192.
What counts as an at-bat
An at-bat is a plate appearance that does not end in a walk, hit by pitch, sacrifice bunt, sacrifice fly or catcher’s interference. That is why a patient hitter with many walks can have a modest average but a high OBP.
Benchmarks
| Stat | Excellent | Good | Around MLB average |
|---|---|---|---|
| AVG | .300 | .270 | .240 to .250 |
| OBP | .390 | .340 | .310 to .320 |
| SLG | .550 | .450 | .390 to .410 |
| OPS | .900 | .800 | .700 to .730 |
League averages move from year to year with rules, ball and pitching changes, so compare players within the same season.
Which stat matters most?
Batting average ignores walks and treats all hits the same. OBP captures how often a hitter avoids making an out, and SLG captures power, so OPS is a better quick summary of offensive value. Advanced metrics such as wOBA and OPS+ go further by weighting each event and adjusting for ballpark and league.
Qualifying for a batting title
In Major League Baseball, a hitter needs at least 3.1 plate appearances per team game, 502 over a 162-game season, to qualify for the batting title.