What Is Slugging Percentage (SLG) in Baseball?
Slugging percentage (SLG) is total bases divided by at-bats. It measures a hitter’s power — the average number of bases they produce per at-bat — by weighting extra-base hits more heavily than singles. It’s a much better power indicator than batting average.
How slugging percentage is calculated
A single is worth one base, a double two, a triple three, and a home run four. Add those total bases up and divide by at-bats. A hitter with 10 total bases in 20 at-bats slugs .500. The maximum possible is 4.000 (a home run every at-bat).
What is a good slugging percentage?
At the MLB level, a rough reference:
| SLG range | Rating |
|---|---|
| .550 and up | Excellent |
| .500 – .549 | Very good |
| .400 – .499 | About average (MLB) |
| below .400 | Below average (MLB) |
SLG in youth & travel baseball
MLB reference points don’t transfer to a 10-year-old. Slugging shifts dramatically by age and level as pitching velocity and field dimensions change. The useful read is a hitter’s SLG against their own age group — which is how GameLense reports it, in the context of their season and division.
How GameLense calculates SLG
GameLense pulls your hits and at-bats straight from GameChanger and computes slugging the correct way — from aggregated totals across the season, not by averaging single-game rates (which quietly distorts the number). It sits alongside OPS, on-base percentage, and quality at-bats for a full picture of a hitter.
Frequently asked questions
What is slugging percentage in baseball?
Slugging percentage (SLG) measures a hitter’s power by counting the average number of bases they earn per at-bat. Unlike batting average, which treats every hit the same, slugging gives more weight to extra-base hits — a double is worth twice a single, and a home run four times.
How is slugging percentage calculated?
SLG = total bases ÷ at-bats, where total bases = singles + (2 × doubles) + (3 × triples) + (4 × home runs). For example, a hitter with 10 total bases in 20 at-bats has a .500 slugging percentage.
What is a good slugging percentage?
At the MLB level, roughly .400 is around league average, .500 is very good, and .550 and up is excellent. In youth and travel baseball the numbers shift a lot by age and level, so SLG is most meaningful compared to a player’s own age group rather than a pro benchmark.
What is the difference between slugging percentage and batting average?
Batting average counts all hits equally (hits ÷ at-bats), while slugging percentage weights hits by how many bases they produce. A player with lots of singles can have a high average but a modest slugging percentage; a power hitter with extra-base hits will have a much higher SLG.
How does slugging percentage relate to OPS?
OPS (On-base Plus Slugging) is simply on-base percentage plus slugging percentage: OPS = OBP + SLG. Slugging is the power half of that combined number.
What is the highest possible slugging percentage?
The maximum is 4.000, which would mean hitting a home run in every single at-bat. In practice even elite MLB seasons top out well below 1.000.
Related baseball stats
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GameLense calculates SLG automatically from your GameChanger data and benchmarks it by age and season.
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