Earned Run Average

Earned run average (ERA ) is a statistic in baseball, indicating how many enemy runs (points) a pitcher allows average in nine innings. In the calculation but are not counted all the runs, which has made this pitcher, but only the so-called Earned Runs. According to the scoring rules only runs than earned runs are counted, which can be achieved without the help of Errors and Passed Balls. Thus, the performance of the defense is to be eliminated, so that the earned run average measures only the quality of pitching. The earned- run average thus indicates how many points would achieve opposing team against this pitcher if this would by pitching a full game (no extra innings ) and his team does not make mistakes on the defensive.

Whether a run is an Earned Run, decides the Official Scorer, by reconstructing the gameplay without Errors and Passed Balls. All runs that will be scored in this fictional game are earned runs. The determination of the Earned Runs is one of the most difficult tasks scorers because of the complex rules.

Although the performance of the defensive can not be completely eliminated, the earned run average is still valid as meaningful statistics and the most important statistics in Pitchingbereich.

ERA is calculated using the formula:


  • Earned Runs Allowed Earned Runs =, which has submitted the pitcher.
  • Innings Pitched = number of innings played during the season a pitcher.