Calculating Baseball Stats - on Base Plus Slugging (OPS)

If you're a baseball fan, you probably are aware of how important statistics are to the game. A casual fan probably understands what most of the most popular statistics measure, but what about some of the more advanced statistics created to measure a players worth? In this article, we'll look at a one of the slightly more advanced statistics, what it means, and how it's calculated. If you do not already have a familiarity with how to calculate batting average, on base percentage, slugging percentage, and total bases, you may want to see my articles on those topics before diving into this material.

OPS, short for "On Base Plus Slugging", is really just the combination of two other statistics; On Base Percentage (OBP) and Slugging Percentage (SLG). As the name suggests, to calculate OPS you add a players Slugging Percentage and On Base Percentage together. For example, a player with a .400 OBP and a .500 SLG would have an OPS of .900. Note the number can be displayed either with the decimal, or without…there is no real consensus yet among statisticians.

So, what does OPS tell us? It gives up a great tool to compare players on their overall offensive contribution. In order to be among the league leaders in OPS, a player must hit for average, display a great batting eye (to collect walks), and hit for power. An OPS over 900 is considered quite good, and an OPS over 1000 is sure be among the league leaders.

In 2005, Derek Lee of the Chicago Cubs led the National League in OPS at 1.080, while Alex Rodriguez of the New York Yankees led the American League at 1.031. Barry Bonds compiled the highest single season OPS ever in 2004 when he turned in an 1.4217 total. Bonds has the 1st, 2nd, 4th, and 8th spots on the all-time single season OPS list, with Babe Ruth at 3rd, 5th, and 6th, 9th, 11th, and 12th. Ted Williams checks in with the 7th and 10th spots. Obviously, these three players are among the most dominant in baseball history. This is reflected in the all time career OPS ranking, where Ruth is number 1 with a 1.1638 mark, Williams #2 at 1.115, and Bonds #4 at 1.0533. Lou Gehrig holds the #3 spot on the list with a 1.0798. You'll notice that I denoted the career leaders out to four decimal points. When dealing with such a big sample size (a career) this is acceptable because you don't want to round numbers off too much.

As you can see, OPS is an interesting statistic to look at when trying to determine a players overall offensive value.