Baseball Calculator
Let's look at the main calculations used in baseball and how they work.
Batting Average Calculator
Batting average is the ratio of hits to at-bats, excluding walks and sacrifice bunts.
Read MoreERA Calculator
ERA is the number of earned runs a pitcher allows per 9 innings, indicating pitching effec...
Read MoreOn-Base Percentage Calculator
On-base percentage is the ratio of reaching base via hits, walks, or hit-by-pitch among pl...
Read MoreSlugging Percentage Calculator
Slugging percentage is the average number of total bases per at-bat (single=1, double=2, t...
Read MoreOPS Calculator
OPS is on-base percentage plus slugging percentage, a sabermetric measure of a hitter's ov...
Read MoreAbout This Category
Baseball statistics are counting totals normalised into rates, and the four here cover the core of a batting line: average, on-base percentage, slugging and OPS, plus earned run average for pitching.
The difference between them is what counts as success. Batting average ignores walks; on-base percentage counts them; slugging weights each hit by its bases; OPS simply adds the last two as a quick summary.
Frequently Asked Questions
Why is on-base percentage higher than batting average?
Because walks and hit-by-pitches count as reaching base but not as at-bats. A patient hitter can add 80–100 points to his average this way.
What is a good OPS?
Around .700 is average, .800 is good and .900 or above is All-Star level. The scale is not a percentage, so .900 means 900 per thousand, not 90 %.
Does ERA count unearned runs?
No. ERA uses earned runs only, which is why a pitcher can allow several runs and still show a low ERA when errors are involved.
Calculators in This Category
Sources & last update
2026-10-19