ERA Calculator
Earned run average for a pitcher, with innings entered the way box scores print them — 6.2 means six innings and two outs.
ERA is earned runs divided by innings pitched, scaled to a full game: nine innings in baseball, seven in most softball and youth leagues.
How the era calculator works
ERA is earned runs divided by innings pitched, scaled to a full game: nine innings in baseball, seven in most softball and youth leagues. Box scores write partial innings as .1 and .2, meaning one and two outs, so 6.2 innings is 6⅔ — the calculator reads it that way.
Formula: ERA = earned runs × innings per game ÷ innings pitched
Worked examples
| Inputs | ERA | Note |
|---|---|---|
| 24 earned runs in 72.2 innings | 2.97 | 2.97 |
| Softball: 10 runs in 35 innings | 2 | 2.00 |
| A perfect month: 0 runs in 30 innings | 0 | 0.00 |
FAQFrequently asked questions
What is a good ERA?
Under 3.00 is very good in the majors and under 2.50 elite; league average has sat between about 3.90 and 4.50 in recent seasons. College and softball run on a different scale because the games and bats differ.
Why is 6.2 innings read as 6⅔?
Box scores record partial innings by outs: .1 is one out, .2 is two. Reading 6.2 as a decimal would understate the innings by nearly half an inning and inflate the ERA.
What is the difference between ERA and RA?
RA counts every run allowed per nine innings; ERA leaves out unearned runs — those that scored because of an error or passed ball. ERA is the standard figure, though RA is arguably fairer to pitchers with poor defences behind them.
Why is softball ERA scaled to seven innings?
A regulation softball game is seven innings, so a full game of pitching is seven; scaling to nine would make softball ERAs look worse than they are. Little League uses six.
Where these figures come from
- World Handicap System — Rules of Handicapping — the score differential and handicap index formula
- International Cricket Council — Playing Conditions — over structure and run-rate definitions
- Major League Baseball — Official Rules — the published definitions for baseball statistics
Last checked: September 2026. Formulas follow the governing bodies where one publishes them — the World Handicap System for golf, the ICC playing conditions for cricket run rates.