Baseball ERA Calculator

Calculate a pitcher's Earned Run Average from earned runs allowed and innings pitched.

Earned Run Average

3.15

Earned Runs per Inning0.350

Earned Run Average vs Earned Runs Allowed

Earned Run Average (ERA)

ERA is the average number of earned runs a pitcher allows per nine innings. It is the most traditional measure of pitching effectiveness.

Formula

ERA = (Earned Runs / Innings Pitched) x 9

Only earned runs count (errors by fielders are excluded). A lower ERA is better. In modern MLB, an ERA below 3.00 is excellent, 3.00-4.00 is above average, and above 5.00 is poor.

Example Calculation

A pitcher allows 35 earned runs in 100 innings.

  1. 01ERA = (35 / 100) x 9 = 0.35 x 9 = 3.15
  2. 02This is an above-average ERA in modern baseball

Frequently Asked Questions

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