How to Calculate OPS

Baseball is a game of stats, and it's never too early to start keeping tack of your own.

In baseball, OPS (on-base plus slugging) is a statistic that combines a player's slugging percentage and on-base percentage. According to Baseball Almanac, the on-base percentage statistic was originally created in the 1950s by Branch Rickey, a former player and baseball executive, and Allan Roth, the first full-time statistician in baseball history. In 1984, on-base percentage was first combined with the slugging percentage statistic to form OPS. Josh Hamilton of the Texas Rangers led the Major Leagues in 2010 with an OPS of 1.044. As of March 2011, Babe Ruth's 1.164 is the highest lifetime OPS (see references 1, 2 and 3).

Instructions

1. Calculate slugging percentage by dividing total bases by total at-bats. Total bases refers to the number of bases accumulated from hits, weighted with a score of one for a single, two for a double, three for a triple and four for a home run. For example, in 2010, Hamilton had 328 total bases and 518 at-bats, giving him a slugging percentage of 0.633.

2. Calculate on-base percentage, which is a sum of hits, bases on balls and hit-by-pitches, divided by at-bats, bases-on-balls, sacrifice flies and hit-by-pitches. Over the course of the season, if a player had 400 at-bats, 100 hits, walked 50 times, got hit by a pitch 10 times and hit 10 sacrifice flies, he would have an on-base percentage of about 0.340. In 2010, Hamilton had an on-base percentage of 0.411.

3. Calculate OPS by simply combining slugging percentage and on-base percentage. Hamilton's 2010 slugging percentage of 0.633 and on-base percentage of 0.411 gave him his OPS of 1.044.

Tips & Warnings

• Consider that the at-bat statistic in step two does not necessarily refer to the amount of plate appearances. For statistical purposes, a batter has had an official at-bat any time he faces a pitcher and does not walk, get hit by a pitch, hit a sacrifice fly or bunt, receive a free base due to interference, finish his at-bat due to the inning ending in another way or is replaced by another batter before he completes his at-bat (see reference 4).

References

• Baseball Almanac: Career Leaders for On Base Plus Slugging
• Baseball-Reference.com: Allan Roth
• MLB.com: Josh Hamilton
• MLB.com: Official Baseball Rules