Calculate Slugging Percentage
While batting average counts a home run the same as a single, slugging percentage takes into account the actual number of bases scored. Despite the name, this statistic is actually an average, not a percentage. A player with high slugging percentage has a high number of bases scored per opportunity at bat.
Contents
[hide]Formula Cheatsheet
- Slugging Percentage (SLG) = Total Bases ÷ At Bats
- Total Bases = Singles + (2 x Doubles) + (3 x Triples) + (4 x Home Runs)
- Total Bases (alternate method) = Hits + Doubles + (2 x Triples) + (3 x Home Runs)
Steps
Calculating Slugging Percentage
- Understand slugging percentage. Also called slugging average, SA, or SLG, this is a player's average number of bases per bat. If a player has an (unrealistic) slugging percentage of 1, their average result was a single.
- This only measures number of bases from hits, not from walks or hit by pitch. Ignoring the bases out of the batter's control makes this a more accurate measure of offensive power.
- Find the number of singles. Most player stats don't include singles, but it's easy to figure out from other stats. First, add Home Runs + Triples + Doubles to get all the hits that aren't singles. Then subtract your answer from the total number of Hits to get the number of Singles.
- For example, Willie McCovey has career stats of 521 Home Runs, 46 Triples, and 353 Doubles, adding up to 920. Subtract 920 from his career Hits of 2211 to get the number of Singles: 1291.
- Calculate the number of bases. Add together (Singles) + (2 x Doubles) + (3 x Triples) + (4 x Home Runs) to get the total number of bases.
- Willie McCovey scored a total number of bases equal to (1291) + (2 x 353) + (3 x 46) + (4 x 521) = 1291 + 706 + 138 + 2084 = 4219.
- Divide your answer by at bats. Divide total bases by the number of at bats to get the slugging percentage.
- Willie McCovey had 8197 At Bats, so his career slugging percentage is 4219 ÷ 8197 = 0.5147 (rounded to 0.515). On average, he scored a little more than one base for every two at bats.
Alternate Method
- Find the total bases with a faster method. The method above is the easiest to understand, but require extra math to find the number of singles. Here's a way to skip that step and find the total bases using Hits instead: Total Bases = Hits + Doubles + (2 x Triples) + (3 x Home Runs).
- This works because one base per Hit takes care of all the singles. Since this also awards one base for each double, you only need to add 1 more base per double to find the total. Similarly, add two extra bases for triples, and three extra for home runs.
- Divide by at bats. Just as before, the slugging percentage is equal to the total bases divided by at bats.
Related Formulas
- Add Slugging Percentage to On Base Percentage. The result, On Base Plus Slugging (OPS), takes into account the most important offensive stats. Baseball statisticians don't consider this accurate, but it's a quick and easy way to compare offensive power.
- OPS+ is a less commonly used statistic that adjusts for the league and park. The formula for OPS+ changes each year to make 100 the league average.
- Adjust slugging percentage for league. This statistic was invented for the baseball encyclopedia Total Baseball, and is rarely used elsewhere. It's a more accurate way to compare players from different years, but it might be hard to dig up the statistics you need to calculate it:
- Adjusted production (APRO) = (On Base Percentage / League OBP) + (Slugging Average / League SA) - 1
- The League stats are the average stats for all players that year.
- The stats are sometimes adjusted to factor in differences between parks as well.
Tips
- Like many baseball stats, this one often shows up without a decimal point. An SLG of 300 means 0.300 bases per at bat, not actually three hundred!
- At bats do not include all plate appearances, only the ones where the batter makes an attempt to score a base. A player's slugging percentage does not change if they get a walk or make a sacrifice play.
