1. What is ERA?

ERA (Earned Run Average) is a statistic in baseball that measures a pitcher's effectiveness, calculated as the average number of earned runs given up by a pitcher per nine innings pitched.

2. How Does the Calculator Work?

The calculator uses the ERA formula:

Where:

• Earned Runs — Runs for which the pitcher is held accountable
• Innings Pitched — Number of innings the pitcher has completed
• 9 — Standard number of innings in a regulation game

Explanation: The formula standardizes the earned runs to a 9-inning game, allowing comparison between pitchers regardless of how many innings they've pitched.

3. Importance of ERA Calculation

Details: ERA is one of the most important statistics for evaluating pitchers. A lower ERA indicates a more effective pitcher. It's used to compare pitchers across different teams and leagues.

4. Using the Calculator

Tips: Enter earned runs (any positive number) and innings pitched (must be greater than 0). Innings can be entered as decimals (e.g., 6.2 for 6⅔ innings).

5. Frequently Asked Questions (FAQ)

Q1: What's considered a good ERA?
A: In modern baseball, an ERA below 4.00 is generally good, below 3.00 is excellent, and below 2.00 is exceptional.

Q2: How do I enter partial innings?
A: Enter as decimals: .1 for ⅓ inning, .2 for ⅔ inning (e.g., 5.1 = 5⅓ innings, 7.2 = 7⅔ innings).

Q3: What's the difference between earned and unearned runs?
A: Earned runs are those that score without the benefit of errors or passed balls. Unearned runs result from defensive mistakes and don't count toward ERA.

Q4: Why multiply by 9 in the formula?
A: This standardizes the statistic to a full 9-inning game, making it easier to compare pitchers regardless of how many innings they've pitched.

Q5: Does ERA account for ballpark differences?
A: No, basic ERA doesn't. For more advanced analysis, metrics like ERA+ adjust for ballpark factors and league averages.