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Earned Run Average or ERA: Your Simple Guide In Baseball

Earned Run Average (ERA)

If you are a baseball fan, I bet you have also studied the ups and downs of the different methods to evaluate the statistics of your favorite baseball player. For about as long as baseball has been played, players, coaches, and fans have had many methods to evaluate players properly. As times change, the practices of evaluating players have evolved.

Since pitchers are very involved in every play, they must have a strong arm and throw the ball accurately. They have generally considered being the most critical asset to a team’s success. But have you ever wondered how pitchers are evaluated in their stats?

If you are still puzzled about how it has to be done, you’re in the right article. In this article, we will discuss Earned Run Average or ERA. Familiar? No worries, we will talk about more in the next few seconds.

What Is Earned Run Average or ERA In Baseball?

In baseball, the job description for a pitcher is relatively simple: to prevent the other team from scoring. Naturally, the most commonly accepted stat for evaluating pitchers involves how effective the pitcher is at preventing runs, which ERA reflects.

Earned Run Average, or ERA, is a statistic used to measures the average number of runs given up by a pitcher throughout a nine-inning game. It does not include runs resulting from mistakes made by other players on the field. The ERA was designed to determine each pitcher’s effectiveness during games where relief pitchers help share the load.

Many people like to focus on a pitcher’s ERA – particularly fantasy baseball fanatics – but a low ERA doesn’t always translate into a pitcher being good or bad.

A pitcher’s ERA doesn’t tell the entire story, as different sets of circumstances can lead to wild swings in what is considered a “normal” ERA and likewise what is considered good or bad. We’ll go further in-depth to explain what an ERA is and how it’s interpreted.

An ERA is expected to consider the performance of both the pitcher and the defense behind him so that he isn’t punished for indigent defense. As a result, two different types of runs that a pitcher can be charged with: earned and unearned runs.

Earned Vs Unearned Runs In Baseball

To better understand the importance and calculation of ERA, we should probably explain what the difference is between the two.

In the simplest terms, an earned run a run that is deemed to be allowed solely due to the pitcher’s pitching ability, while an unearned run is a run that would not or likely would not have scored without the benefit of an error or passed ball.

The idea is that the lower the ERA, the better. The chart below will help give you an idea of what good, average, and lousy ERAs in major League Baseball.

RatingEarned Run Average (ERA)
Exceptional2.99 and under
Excellent3.00 – 3.50
Above Average4.00 – 4.50
Averageabove 5.00
Below Average6.00 or 7
Poor6.00 and above

Let’s analyze the chart. The lower the ERA, the better the pitcher is considered.

  • 2.99 and under – We’re talking rock solid pitcher here. If you’ve got a pitcher on the hill that gives up an average of 3 runs or less per game, you’re going to win a lot of fun.
  • 3.00 to 3.50 – These are significant ERA’s. Very sustainable and very solid.
  • 4.00 to 4.50 – This would be considered to be an average ERA. When betting, it’s probably best to make sure your offense can score many runs because your pitcher is/can be a liability for you.
  • ERA’s above 5.00 – These can be solid go against considering the circumstances.
  •  6.00 or 7.00 – An old pitcher who’s lost his stuff is on the mound, a guy that’s recently come off an injury, or a young player such as a rookie is pitching.

With all this being said, be careful. An ERA isn’t the sole factor in capping baseball. Keep in mind some guys are more comfortable at home court than they are on the road and likewise.

It’s important to remember that a batting lineup in high school is different from the depth of a batting lineup in college or the Major Leagues. We also need to consider the lack of depth in a high school baseball lineup, and high school pitchers tend to have lower ERAs.

RatingEarned Run Average (ERA)
Exceptional0.00 – 0.60
Excellent0.60 – 1.20
Above Average1.20 – 2.00
Average2.00 – 3.00
Below Average4.00 – 5.00
Far Below Average5.00 and above

What Is ERA Formula?

ERA can be a little tricky to calculate at first because there are three numbers to take into consideration, but once you get the hang of calculating it a few times it shouldn’t be too difficult.

A pitcher’s ERA is calculated by dividing the total number of earned runs allowed by the total number of innings pitched, then multiplying the total result by nine.

The earned run average formula is as follow:

ERA = (Earned Runs / Innings Pitched) * Game Innings

The terms in the baseball era formula;

  • Earned Runs (ER): it indicates a run in baseball that scores without the benefit of an error before the fielding team has had a chance to make the 3rd putout of the inning.
  • Innings Pitched (IP): it is a pitching statistic in baseball that measures the number of innings a pitcher remains in a game as there are (3 outs) in an inning, with each out recorded indicates 1/3 of an inning pitched.
  • Game Innings: it is the total innings in a game, typically, in baseball, this value is equal to 9.

 ERA Only Calculates Earned Runs

An important piece to remember is that a pitcher’s ERA is only calculated based on that pitcher’s earned runs. When a runner scores on an error, that run does not count towards a pitcher’s ERA.

So, this stat does not penalize a pitcher when a fielder makes a mistake. This is one of the main reason coaches love to look at a pitcher’s ERA – because coaches can infer that pitchers with a lower ERA are more challenging to hit than pitchers with a high ERA. 

Some fans and critics see this as the worst way to evaluate a pitcher since pitchers are not penalized when runs are scored as a result of a defensive error 

What Is A Good Career ERA In Baseball?

Most pitchers in the Major Leagues will last about 5 to 6 years, but what does a sound ERA look like for them for those best pitchers?

In general, an ERA in the range of 4.00 – 5.00 is considered a sound career ERA, with the best pitchers being below 2.00.

According to Baseball Almanac, Ed Walsh is credited with holding the career record for ERA with 1.82.

Advantage Of Pitchers With A High ERA

One of the most important reasons many people like to concentrate on a pitcher’s ERA is that ERA is a solid reliable indicator of how many runs the pitcher allows.

Like most other sports, baseball is won when one team gets more runs than another team. So it does make sense that a pitcher with a lower ERA can have more runs and eventually have a much better chance to win the game.

What Is The Lowest Era Ever?

In 1880, Tim Keefe was posted the lowest single-season ERA that is 0.86 ERA in 105 innings pitched for the National League’s Troy Trojans under the supervision of his closest competitor by .52 runs. Dutch Leonard’s 0.96 ERA is a single-season record in the American League.

History Of ERA

The history of ERA stretches back to the 19th Century when writer and statistician Henry Chadwick began to suspect that the win-loss record was not a complete indicator of a pitcher’s effectiveness.

Chadwick argued that simple winning percentage relied too much on factors beyond a pitcher’s control — such as the team’s offensive output and fielding prowess — to be used as a fair judgment of a pitcher’s value. Chadwick developed ERA to get a closer read on a pitcher’s actual value to his team.

Who Has The Lowest Career Era In Mlb History?

Albeit over a shorter career, Addie Joss’ career Earned run average of 1.89 is second all-time to Ed Walsh, and his 0.968 WHIP is the lowest ratio on the count. Joss’ pitched for the Cleveland Naps of the American League.

Earned Run Average or ERA: Your Simple Guide In Baseball

Final Words

The definition of a sound ERA varies from year to year, as with the batting average. ERA tells you how consistent and dominant a pitcher is. It also gives you an idea of how  good a pitcher is by getting a strikeout when they need or picking his team up after making an error;  though it has its gray area, we cannot deny that coaches can create a visual plan that can give the best strategy for the next incoming big game.