Sports & Gaming · Statistics · Descriptive Statistics
Slugging Percentage (SLG) Calculator
Calculate a baseball batter's slugging percentage (SLG) from singles, doubles, triples, home runs, and at-bats.
Calculator
Formula
SLG equals total bases divided by at-bats. 1B = singles, 2B = doubles, 3B = triples, HR = home runs, AB = at-bats. Each hit type is weighted by the number of bases it represents.
Source: MLB Official Baseball Rules, Rule 9.22 — Major League Baseball, 2023.
How it works
Slugging percentage is calculated by dividing a batter's total bases by their total at-bats. Each hit type contributes to total bases according to how many bases it is worth: a single counts as 1 base, a double as 2, a triple as 3, and a home run as 4. The formula is: SLG = (1×1B + 2×2B + 3×3B + 4×HR) ÷ AB.
Unlike batting average, which treats all hits equally, slugging percentage rewards power hitting. A player with 100 at-bats who hits only home runs would have a perfect SLG of 1.000, while one who hits only singles would have a maximum SLG of 1.000 as well — but only if every at-bat resulted in a hit. In practice, elite sluggers typically post SLG values above .500, while the MLB league average hovers around .400.
SLG is widely used in sabermetrics as a component of OPS (On-Base Plus Slugging), which combines on-base percentage and slugging percentage into a single offensive rating. It also feeds into advanced metrics like wRC+ and OPS+, making it a foundational statistic for player evaluation and comparison across eras.
Worked example
Example: Calculating SLG for a full season
Suppose a batter has the following stats over a 162-game season:
- Singles (1B): 85
- Doubles (2B): 28
- Triples (3B): 4
- Home Runs (HR): 32
- At-Bats (AB): 520
Step 1 — Calculate total bases:
(1 × 85) + (2 × 28) + (3 × 4) + (4 × 32) = 85 + 56 + 12 + 128 = 281 total bases
Step 2 — Divide by at-bats:
SLG = 281 ÷ 520 = .540
A slugging percentage of .540 is excellent — this level of production would place the batter among the top power hitters in the league. For reference, Babe Ruth's career SLG of .690 remains the all-time MLB record.
Limitations & notes
Slugging percentage does not account for walks, hit-by-pitches, or stolen bases, which means it provides an incomplete picture of a batter's total offensive value — this is why it is typically paired with on-base percentage (OBP) to form OPS. Additionally, SLG is sensitive to ballpark factors: hitter-friendly parks with short fences inflate home run and extra-base hit totals, so cross-park or cross-era comparisons should use park-adjusted metrics like SLG+ or Isolated Power (ISO). The statistic also treats all at-bats equally regardless of situational context (e.g., bases loaded vs. bases empty), and it does not measure baserunning or defensive contributions. Finally, small sample sizes — such as fewer than 100 at-bats — make SLG highly volatile and less reliable as a performance indicator.
Frequently asked questions
What is a good slugging percentage in MLB?
In modern MLB, a slugging percentage of .450 or above is considered above average, .500+ is excellent, and .550+ is elite. The MLB league average typically falls around .400. All-time great seasons have reached .700+, with Babe Ruth holding the all-time career record at .6897.
What is the difference between slugging percentage and batting average?
Batting average (BA) treats all hits equally — a single counts the same as a home run. Slugging percentage weights each hit by the number of bases it produces, giving doubles twice the value of singles, triples three times, and home runs four times. This makes SLG a much better measure of a batter's power and run-production potential.
Can a slugging percentage be greater than 1.000?
No. The theoretical maximum is exactly 1.000, achieved only if a batter hits a home run on every single at-bat (4 bases ÷ 1 AB = 4.000 is impossible because other at-bat outcomes bring the average down). In practice, the highest single-season SLG ever recorded is Barry Bonds' 0.863 in 2001. Values above 1.000 are mathematically impossible since the maximum bases per at-bat is 4.
Do walks count in slugging percentage?
No. Walks (bases on balls), hit-by-pitches, and sacrifices are not included in the slugging percentage calculation — neither as hits nor as at-bats. Only official at-bats and the hits that result from them are counted. This is a key distinction from on-base percentage (OBP), which does include walks.
What is the difference between SLG and OPS?
OPS (On-Base Plus Slugging) is the sum of a player's on-base percentage (OBP) and slugging percentage (SLG). While SLG measures power hitting, OBP measures a player's ability to reach base via hits, walks, and hit-by-pitches. Adding them together gives OPS, a simple but powerful all-around offensive rating. An OPS of .800 is above average; .900+ is excellent; 1.000+ is elite.
How does Isolated Power (ISO) relate to slugging percentage?
Isolated Power (ISO) is derived from SLG by subtracting batting average: ISO = SLG − BA. It strips away the contribution of singles to measure only extra-base hit power. A player with a .300 BA and .550 SLG has an ISO of .250, which is considered elite. ISO is useful for isolating raw power from a player's overall hit production.
Last updated: 2025-01-30 · Formula verified against primary sources.