Slugging Percentage Calculator
Turn a hitting line into slugging percentage — the power-weighted cousin of batting average.
Power, not just contact
Slugging weights each hit by the bases it earns, so extra-base hits count for more.
It is per at-bat
Walks and sacrifices are not at-bats, so they never appear in the denominator.
What is slugging percentage?
Total bases per at-bat
Slugging percentage (SLG) measures a hitter's power by counting how many bases they earn per at-bat. Unlike batting average, which treats every hit the same, slugging rewards extra-base hits: a double is worth twice a single, a triple three times, and a home run four times. According to the official baseball rules, it is simply total bases divided by at-bats, and it has become one of the headline numbers on every player's stat line.
Slugging percentage is total bases over at-bats, where each hit is weighted by the bases it produces.
SLG = (1B + 2×2B + 3×3B + 4×HR) / ABHere 1B, 2B, 3B, and HR are singles, doubles, triples, and home runs, and AB is at-bats. The numerator is total bases — the sum of every base earned on hits. Because a home run counts four times as much as a single, slugging separates power hitters from contact hitters in a way batting average never can. A perfect game of all home runs would slug 4.000, the theoretical maximum, while a season around .450 already marks a strong power year.
Take a hitter with 500 at-bats: 100 singles, 30 doubles, 5 triples, and 25 home runs.
Weight each hit
Singles 100×1 = 100, doubles 30×2 = 60, triples 5×3 = 15, home runs 25×4 = 100.Add up total bases
100 + 60 + 15 + 100 = 275 total bases.Divide by at-bats
275 ÷ 500 = 0.550.Compare to average
With 160 hits, the batting average is 160 ÷ 500 = .320 — slugging is higher because of all that extra-base power.
Slugging is one of a family of rate stats, and it is most useful read alongside the others.
Batting average
Hits per at-bat. It measures how often you reach on a hit, but treats a single and a home run identically.
Slugging percentage
Total bases per at-bat. It captures power, rewarding doubles, triples, and home runs.
OPS
On-base plus slugging. Adding on-base percentage to slugging gives a quick all-round value number, which is why OPS is so widely quoted.
According to reference sites such as Baseball Reference, a league-average slugging percentage usually sits around .400, the best power hitters push past .550, and the all-time single-season records sit above .800. If you want to compare records as plain percentages instead, our win percentage calculator handles team standings, and our reverse percentage calculator works back from a known result to the original number.
The slugging percentage is a rate, not a true percentage, so it is read like batting average — .550 means 0.55 bases per at-bat on average. The total bases figure shows the raw power output that drove it, and the batting average sits beside it so you can see how much of the slugging comes from extra-base hits rather than volume of singles. Two hitters can share a batting average yet have very different slugging numbers: the one with more doubles and home runs slugs higher. Because the denominator is at-bats rather than plate appearances, walks neither help nor hurt slugging, which is why power hitters who also draw walks are best judged on on-base plus slugging together.
The arithmetic is exact; the context is everything.
A rate stat, read it in context
Slugging percentage rewards power but ignores walks, stolen bases, and defence, so it is never a complete picture of a hitter on its own. It also depends on era and ballpark — a .500 slugging means more in a low-scoring season than a high-scoring one. This calculator computes the standard slugging formula from the hits you enter; it does not adjust for league, park, or quality of opposition. Use it to compute and compare slugging numbers on a like-for-like basis, and pair it with on-base percentage for a fuller view of a hitter's value.