On-Base Percentage Calculator
Calculate on-base percentage (OBP) from hits, walks, HBP, at-bats, and sacrifice flies. Understand the sabermetric significance and compare to league benchmarks.
Slugging Percentage Calculator
Calculate slugging percentage (SLG) and OPS from your batting stats. Break down total bases by hit type and compare to MLB benchmarks for power-hitting analysis.
Optional: Add Walks/HBP/SF for OBP & OPS
Slugging Percentage
0.610
EliteOPS: 1.006(MVP-Level)
SLG⧉
0.610
Elite
Batting Average⧉
0.320
Arithmetic average of values
ISO (Isolated Power)⧉
0.290
Elite power
Total Bases⧉
305
Sum of all values
Total Hits⧉
160
Sum of all values
OBP⧉
0.396
OPS⧉
1.006
MVP-Level
TB per Hit⧉
1.91
Total Bases Breakdown
Singles (1 TB each)90 hits → 90 TB (29.5%)
Doubles (2 TB each)30 hits → 60 TB (19.7%)
Triples (3 TB each)5 hits → 15 TB (4.9%)
Home Runs (4 TB each)35 hits → 140 TB (45.9%)
Your Slash Line
0.320 / 0.396 / 0.610
BA / OBP / SLG — OPS: 1.006
SLG Classification Benchmarks
| Tier | SLG Range | Example Players |
|---|---|---|
| ▶ Elite | .550+ | Babe Ruth, Barry Bonds |
| Excellent | .500–.549 | Mike Trout, Manny Ramirez |
| Above Average | .450–.499 | Strong everyday hitters |
| Average | .400–.449 | League average (~.410) |
| Below Average | .350–.399 | Light-hitting players |
| Poor | .300–.349 | Weak contact, no power |
| Very Poor | Below .300 | Replacement level or worse |
⚠️ Disclaimer: This calculator uses the official MLB slugging percentage formula for educational and analytical purposes. Actual MLB statistics may differ due to scoring rule interpretations. Always verify with official sources for record-keeping purposes.
Planning notes, formulas, and examples
About the Slugging Percentage Calculator
Slugging percentage (SLG) measures power hitting by dividing total bases by at-bats. Unlike batting average, which treats every hit equally, SLG assigns extra weight to extra-base hits: a double is worth twice a single, a triple three times, and a home run four times. This makes SLG the standard measure for evaluating a hitter's raw power output.
Our Slugging Percentage Calculator computes SLG from your hit breakdown (singles, doubles, triples, home runs) using the formula TB / AB, where TB = 1B + 2×2B + 3×3B + 4×HR. It also calculates OPS (On-base Plus Slugging), the most popular combined offensive metric in baseball, by adding your OBP and SLG together. ISO (Isolated Power = SLG − BA) is included to show pure extra-base power.
Whether you're evaluating power hitters for a fantasy draft, tracking your own slow-pitch softball performance, or studying the evolution of the long ball in baseball history, it shows comprehensive power-hitting analytics.
When This Page Helps
SLG captures something batting average completely ignores: how far the ball travels. A .280 hitter with 40 home runs and a .560 SLG is a vastly different player from a .280 hitter with 5 home runs and a .350 SLG. Combined with OBP to form OPS, slugging percentage gives you the best quick-and-dirty assessment of total offensive value available. ISO further isolates the pure extra-base component.
How to Use the Inputs
- Enter total at-bats (AB) for the period you want to analyse.
- Enter singles (1B), doubles (2B), triples (3B), and home runs (HR).
- Optionally enter walks (BB), HBP, and sacrifice flies to also calculate OBP and OPS.
- View SLG, total bases, ISO, and OPS quickly.
- Check the total-bases breakdown to see the power contribution of each hit type.
- Compare your SLG to MLB benchmarks in the classification table.
Formula used
Total Bases (TB) = 1B + (2 × 2B) + (3 × 3B) + (4 × HR). Slugging Percentage (SLG) = TB / AB. Isolated Power (ISO) = SLG − BA = (TB − H) / AB. OPS = OBP + SLG. Hits (H) = 1B + 2B + 3B + HR. BA = H / AB. OBP = (H + BB + HBP) / (AB + BB + HBP + SF).Example Calculation
Result: SLG: .610
Total hits = 90 + 30 + 5 + 35 = 160. BA = 160 / 500 = .320. Total bases = 90 + (2×30) + (3×5) + (4×35) = 90 + 60 + 15 + 140 = 305. SLG = 305 / 500 = .610 — wait, let's recalculate: 90 + 60 + 15 + 140 = 305, but check singles: 1B=90 means 90 TB from singles. Total = 305; 305/500 = .610. ISO = .610 − .320 = .290, indicating elite power. Home runs alone account for 140 of 305 total bases (45.9%).
Tips & Best Practices
- SLG above .450 is considered good in MLB; above .500 is excellent; above .550 is elite.
- ISO (SLG − BA) isolates pure extra-base power. Average ISO is ~.140; elite power hitters exceed .250.
- OPS above .800 is good; above .900 is excellent; above 1.000 is MVP-calibre.
- Home runs deliver the most total bases per hit (4 TB each), making HR hitters dominate SLG leaderboards.
- SLG can theoretically range from 0.000 (no hits) to 4.000 (home run every at-bat).
- The "slash line" (BA/OBP/SLG) is the standard shorthand for a player's offensive profile.
- SLG does not account for walks; a player who walks 100 times gets zero SLG credit for those plate appearances.
The Evolution of Power Metrics in Baseball
Slugging percentage has been an official MLB statistic since 1923 but gained prominence in the sabermetric era starting in the 1980s. Bill James and other early sabermetricians recognised that traditional BA undervalued extra-base power. The development of OPS in the 1980s and wOBA in the 2000s further refined how we measure offensive production, but SLG remains the cornerstone of power evaluation.
Understanding the Slash Line
The "slash line" — BA/OBP/SLG — has become the standard shorthand for describing a player's offensive profile. For example, .300/.380/.520 tells you: strong contact (.300 BA), good plate discipline (.380 OBP), and excellent power (.520 SLG). The OPS at the end (.900) confirms elite overall offense. When you see Mike Trout's career .303/.413/.587 line, you immediately know he excels at all three dimensions.
ISO: Isolating Pure Power
Isolated Power (ISO = SLG − BA) is one of the cleanest power metrics available. By subtracting BA from SLG, you remove the single-hit component and see only extra-base production. Two players can have identical .450 SLGs but very different ISOs: one might be a .310 hitter with a .140 ISO (contact-oriented) while the other is a .200 hitter with a .250 ISO (power-dependent).
Total Bases: The Foundation of SLG
The total bases (TB) leaderboard has historically been dominated by players who combine high contact rates with power. The single-season record is 457 TB by Babe Ruth in 1921. In the modern era, 350+ TB is exceptional. Understanding the TB breakdown — how much comes from singles vs. doubles vs. home runs — reveals a hitter's profile and approach.
Sources & Methodology
Last updated:
Methodology
This worksheet uses standard baseball stat definitions and simple derived rates to place a box-score line into a familiar benchmark frame. It is a descriptive stat aid rather than a scouting model.
Sources
- MLB Glossary of Statistics (Major League Baseball) — Official definitions for batting and pitching statistics.
- Baseball-Reference Glossary (Sports Reference) — Common historical/statistical definitions and abbreviations.
- FanGraphs Glossary (FanGraphs) — Sabermetric context for rate stats and modern benchmarks.
Frequently Asked Questions
In modern MLB, the league average SLG is around .395–.415. A good SLG is .450+, very good is .500+, and elite is .550+. For context, the all-time single-season record is Barry Bonds' .863 in 2001 (73 home runs). Anything above .600 in a full season is exceptional.
Batting average treats all hits equally (1 for 1). Slugging percentage weights hits by total bases: a single = 1, double = 2, triple = 3, home run = 4. So a player who hits .300 with all singles has a .300 SLG, while a player who hits .300 with all home runs would have a 1.200 SLG. The difference reveals power.
ISO = SLG − BA. It strips out singles to show only the extra-base component of a hitter's power. A player hitting .280 with a .500 SLG has an ISO of .220. League average ISO is about .140. Elite power hitters reach .250+. ISO is useful for comparing power independent of contact rate.
OPS (On-base Plus Slugging) simply adds OBP and SLG. Despite its mathematical imperfection (adding rates with different denominators), OPS correlates very well with run production and is easy to calculate. An .800 OPS is good, .900 is excellent, and 1.000+ is MVP-level. It's the most widely used single offensive metric.
Yes! The theoretical maximum is 4.000 (home run every at-bat). In practice, single-month or short-stretch SLGs can exceed 1.000. Barry Bonds slugged .863 over a full 2001 season. Any player hitting mostly extra-base hits in a small sample can temporarily exceed 1.000.
Babe Ruth holds the all-time career SLG record at .690. Ted Williams is second at .634, followed by Lou Gehrig (.632). Among modern players, Mike Trout (.587) and Albert Pujols (.544) rank among the highest. Ruth's .690 career SLG is so far ahead it may never be approached.
SLG is specifically designed to measure hitting power per at-bat. Walks are not at-bats (they're plate appearances), so they don't appear in the SLG formula. This is by design: SLG isolates what happens when a batter swings and makes contact. OBP captures the walk component, and OPS combines both perspectives.
wRC+ (weighted Runs Created Plus) is a park-adjusted and league-adjusted run creation metric scaled to 100 (where 100 = league average). Unlike OPS, it properly weights each offensive event based on actual run values and adjusts for ballpark effects. A 150 wRC+ means the batter creates 50% more runs than average. It is one of the clearest all-in-one modern offensive metrics.
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