About the Slugging Percentage Calculator
This slugging percentage calculator measures a hitter’s power by weighting every hit by the bases it earns. Enter singles, doubles, triples, home runs and official at-bats, and it returns slugging percentage (SLG), total bases, batting average, isolated power (ISO) and the share of hits that went for extra bases.
Slugging is useful when batting average alone hides the difference between a singles hitter and a power bat: two players can both hit .280, but one with 35 home runs will slug far higher. Coaches, fantasy managers and players tracking their own season use SLG to compare run-producing ability, and it is half of OPS.
Despite the name, slugging percentage is not a percentage — it is total bases per at-bat, so it can range from 0 to 4.000. Walks and hit-by-pitches do not count, because they are not at-bats.
With the default inputs, the slugging percentage (slg) is 0.519. Change any value above to recalculate instantly.
How to use the slugging percentage calculator
- 1Enter the hitter’s singles, doubles, triples and home runs.
- 2Enter official at-bats (not plate appearances).
- 3Read slugging percentage and total bases.
- 4Use ISO to compare raw power between hitters with different averages.
Formula and method
Total bases credit one base for a single, two for a double, three for a triple and four for a home run. Slugging percentage divides total bases by official at-bats, so it measures bases gained per at-bat. Because a home run in every at-bat would be 4 bases each time, the maximum possible SLG is 4.000.
Batting average is hits ÷ at-bats, and isolated power (ISO) subtracts batting average from slugging to strip out singles and show only extra-base power. Walks, hit-by-pitches and sacrifices are excluded from slugging because they are not at-bats.
- 1B, 2B, 3B, HR
- Singles, doubles, triples and home runs
- TB
- Total bases
- AB
- Official at-bats
- AVG
- Batting average (hits ÷ AB)
Worked examples
Middle-of-the-order power hitter
95 singles, 32 doubles (64 bases), 3 triples (9) and 28 home runs (112) add up to 280 total bases. Dividing by 540 at-bats gives a .519 slugging percentage; subtracting the .293 average leaves an ISO of .226.
Singles hitter
168 hits produce only 207 total bases because almost all are singles. The .280 average is solid, but a .345 SLG and .065 ISO show very little power.
One game: home run and a double in 4 at-bats
A double (2 bases) and a home run (4) make 6 total bases in 4 at-bats, a 1.500 slugging percentage for the game.
Frequently asked questions
How do you calculate slugging percentage?+
Add up total bases — 1 per single, 2 per double, 3 per triple, 4 per home run — and divide by official at-bats. For example, 280 total bases in 540 at-bats is a .519 slugging percentage.
What is a good slugging percentage?+
In recent MLB seasons the league-average SLG has been about .400. A slugging percentage of .450 is good, .500 is excellent and .550 or higher is typical of the game’s best power hitters.
Why is slugging percentage not really a percentage?+
It is an average of total bases per at-bat, not a share out of 100. It can therefore exceed 1.000 and reach a maximum of 4.000 if every at-bat were a home run.
Do walks count in slugging percentage?+
No. Walks, hit-by-pitches, sacrifice bunts and sacrifice flies are not at-bats and earn no total bases, so they do not affect slugging. On-base percentage is the stat that rewards walks.
What is the difference between SLG and ISO?+
SLG counts every base from every hit. ISO (isolated power) subtracts batting average from SLG, which removes singles and leaves only the extra bases from doubles, triples and home runs.