Earned Run Average
Earned Run Average
Result
Note! This is not a diagnosis. The calculations that are provided are estimates based on averages.
Earned Run Average ?
What is Earned Run Average?
Major League pitchers are often evaluated using their earned run average, or ERA. This figure shows how many runs a pitcher allows per nine innings.
Earned runs are considered any runs scored against a pitcher that are not due to fielding errors. For example, if Tim Lincecum allows three solo home runs and then a fielding error allows the second run, he is only responsible for the first three runs, which are considered “earned”.
Earned Run Average Formula
The formula for calculating earned run average is:
ERA = (Earned Runs Allowed / Innings Pitched) * 9
How to Calculate Earned Run Average?
To find a pitcher’s earned run average, divide the earned runs he has allowed by the number of innings he has pitched. This gives him his average earned runs per inning. Then, multiply that number by nine (the length of a standard game) and see how many runs he will give up in nine innings.
How to Calculate Earned Run Average for a Game?
Suppose a pitcher gives up 3 earned runs in 6 innings. Here’s the calculation:
- Divide earned runs allowed (3) by innings pitched (6). 3 ÷ 6 = 0.5
- Multiply 0.5 by 9. 0.5 × 9 = 4.5
The pitcher’s ERA for that game would be 4.50.
As a real-world example, consider Paul Skanes’ first career start, where he pitched 4 innings and gave up 3 earned runs. Here’s how to calculate his ERA:
- Divide Skanes’ earned runs (3) by innings pitched (4). 3 ÷ 4 = 0.75
- Multiply 0.75 by 9. 0.75 × 9 = 6.75
Paul Skans recorded a 6.75 ERA in his first career start.
How to Calculate Earned Run Average for Multiple Games?
You can also calculate a pitcher’s ERA over multiple games, seasons, or his entire career using the same formula.
For example, Cy Young pitched 7356 innings and allowed 2147 earned runs. Here’s how to calculate his career ERA:
- Divide total earned runs (7356) by total innings allowed (2147). 2147 ÷ 7356 = 0.292
- Multiply 0.292 by 9. 0.292 × 9 = 2.628
- Round 2.628 to 2.63, since ERA is usually shown with two decimal places
Cy Young’s career ERA is 2.63.
FAQs
Q1. What is a good earned run average in baseball?
A good ERA generally depends on the league and era, but in Major League Baseball (MLB), a score below 3.00 is often considered excellent. Pitchers with an ERA between 3.00 and 4.00 are considered strong, while a score above 5.00 may indicate struggle. In 2025, as advanced analytics become more popular, ERA+ (adjusted earned run average) is also trending as a good way to comparatively evaluate pitchers across different ballparks and seasons.
Q2. Why is earned run average important for fantasy baseball?
In fantasy baseball, ERA is one of the main statistics used to measure a pitcher’s performance. A lower ERA means that the pitcher is more reliable and allows fewer runs. With fantasy sports rapidly growing in 2025, ERA is one of the top indicators for selecting strong pitchers in your fantasy team lineup.
Q3. What is the difference between earned run average and WHIP?
ERA measures how many runs a pitcher gives up per nine innings, while WHIP (Runs Pitched on Walks and Hits) measures how many baserunners a pitcher allows. Simply put, ERA tracks runs scored and WHIP tracks runners allowed. Many modern fans and analysts look at both stats together for a clearer view of a pitcher’s skill.
Q4. Can a pitcher have a 0.00 earned run average?
Yes, but only if the pitcher has not yet given up any earned runs. For example, many rookie pitchers in the 2025 MLB season started their careers with a 0.00 ERA after just a few games. However, as the season continues and they pitch more innings, their ERA usually changes based on performance.
