How to Calculate:
9 x Earned Runs Allowed / Innings Pitched = ERA
Earned Run Average (ERA) is the most popular stat to calculate just how well a pitcher is pitching. The stat will calculate how many earned runs a pitcher will give up in a nine inning span. The stat is determined by dividing earned runs by innings pitched multiplied by 9.
Say a player has pitched 150 innings and given up just 25 earned runs then their ERA would be 1.50.