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 standard ERA formula:

Where:

• \( Earned\ Runs \) — Runs scored without benefit of errors
• \( Innings\ Pitched \) — Total innings pitched
• \( 9 \) — Standard number of innings in a regulation game

Explanation: The formula scales the earned runs to a standard 9-inning game to allow comparison between pitchers.

3. Importance of ERA

Details: ERA is one of the most important metrics for evaluating pitcher performance. Lower ERA values indicate better performance. A good ERA is typically below 4.00 in modern baseball.

4. Using the Calculator

Tips: Enter total earned runs allowed and total innings pitched. Innings can be entered with decimal points (e.g., 6.2 for 6⅔ innings).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between ERA and RA?
A: ERA only counts earned runs (without errors), while RA (Run Average) counts all runs allowed.

Q2: What is considered a good ERA?
A: Below 4.00 is generally good, below 3.00 is excellent, and below 2.00 is exceptional.

Q3: Why multiply by 9 in the formula?
A: This standardizes the statistic to a full 9-inning game regardless of actual innings pitched.

Q4: How should partial innings be entered?
A: Enter as decimals - 0.1 for ⅓ inning, 0.2 for ⅔ inning (e.g., 6.2 means 6 and ⅔ innings).

Q5: Does ERA account for ballpark factors?
A: No, ERA is a raw statistic. For park-adjusted metrics, see ERA+ or similar advanced stats.