ERA Calculator

Earned run average is earned runs times the game length, divided by innings pitched. With a 9-inning game, ERA = (earned runs x 9) / innings pitched. For example, 30 earned runs over 180 innings is (30 x 9) / 180 = 1.50.

In box scores, innings pitched counts outs in thirds, not tenths. A .1 means one out, or one third of an inning, and .2 means two outs, or two thirds. So 6.2 innings is really 6 and 2/3, about 6.667 in decimal form. Enter that decimal here, not 6.2.

Because the tool treats the number as a true decimal. Typing 6.2 is read as six and one fifth of an inning, not six and two thirds, which nudges the result. Convert box-score thirds to their decimal, such as 6.333 or 6.667, for an accurate figure.

An earned run scores without the help of an error or a passed ball. Runs that cross the plate only because of defensive mistakes are unearned and are left out of ERA, which is why ERA reflects a pitcher's own performance more than raw runs allowed.

In modern Major League Baseball, an ERA under 3.00 is excellent, the low 4.00s is roughly league average, and above 5.00 is poor. Context such as ballpark, league and the run-scoring environment of the era shifts those bands.

ERA traditionally scales to nine innings, but some leagues, youth divisions and doubleheaders use seven-inning games. Setting Game length to 7 scales the rate to those shorter contests so pitchers can be compared on equal terms.

The ERA card shows two decimal places, matching how leagues publish the stat. The underlying division is exact, so only the displayed value is rounded, and a figure like 2.025 appears as 2.03.

No. ERA ignores defense quality, inherited runners charged to another pitcher and luck on balls in play. Analysts pair it with stats like FIP, WHIP and strikeout rate to build a fuller picture.

Yes. The calculation runs entirely in your browser, so the numbers you enter are never sent to a server or saved anywhere.