Modern statistics are changing the way MLB players are evaluated.
In MVP discussions, fans will more often hear WAR (wins above replacement) than they hear batting average. On the defensive side, errors and fielding percentage have effectively been replaced by defensive runs saved and outs above average.
OPS isn't as analytical as some of these stats. In fact, it's been around for a very long time. It is, however, quickly becoming a much-preferred alternative to batting average when it comes to one number that defines how good a hitter a given player might be.
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Here are the details on OPS, its meaning, and what constitutes a strong OPS.
What is OPS in baseball?
OPS stands for on-base percentage plus slugging percentage. A hitter's OPS is his on-base percentage and slugging percentage added together. That means the number includes the value of a player reaching base often, while also quantifying what kind of hits a player is producing.
Batting average doesn't weight a player's hits the same way OPS does. For example, a player with 27 singles in 100 at-bats would have a .270 average. A player with 27 home runs in 100 at-bats would also have a .270 average. The player with 27 home runs has decisively added more value than the player with 27 singles, and he would have a dramatically higher OPS as a result.
What is slugging percentage?
Slugging percentage is certainly the more complicated of the two stats that go into OPS. Ultimately, a player's slugging percentage takes into account his total bases. Walks and hit-by-pitches are not factored in; only hits.
When calculating slugging percentage, singles count as one, doubles are multiplied by two, triples are multiplied by three, and home runs are multiplied by four. The resulting numbers are added together a divided by a player's total number of at-bats.
Unlike on-base percentage or batting average, slugging percentage recognizes that not all hits are the same and is a good tool for evaluating a player's power. A player who hits 45 home runs will come away with a pretty strong slugging percentage regardless of whether he hits .200 or strikes out often (looking at you, Kyle Schwarber).
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What is on-base percentage?
On-base percentage measures how often a hitter reaches base, per plate appearance. Hits, walks and hit-by-pitches are included in a hitter's on-base percentage, but a hitter does not credit for reaching base on an error, dropped third strike, or fielder's choice.
If a player reaches base by either hit, walk or hit-by-pitch 34 times out of 100 plate appearances, his OBP will be .340. To get a player's OPS, that number is added to his slugging percentage.
What is a good OPS in baseball?
OPS isn't weighted, unlike OPS+ and wRC+, so the average OPS varies by year. This season, the league average OPS was .734 OPS. In 2022, however, the average OPS was only .706. In almost all cases, though, any OPS above .800 indicates a player is a good-to-very-good hitter.
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A 1.000 OPS is essentially the holy grail of the stat. While the value of a 1.000 OPS varies by season, only a small handful of qualified hitters tend to reach the mark or even come very close each year. This season, Shohei Ohtani, Corey Seager and Ronald Acuna Jr. posted an OPS north of 1.000, while Matt Olson and Mookie Betts were both above .980.
It's also fair to scrutinize OPS by position. For example, catchers don't tend to hit as well as shortstops, so a .750 OPS out of a full-time catcher might satisfy a team much more than a .750 OPS from a full-time shortstop.
