What is a good ERA in baseball?

In Major League Baseball, an ERA under 3.00 is considered excellent, 3.00–4.00 is above average, 4.00–5.00 is average, and above 5.00 is below average. Standards differ in amateur and youth leagues.

How do partial innings work in ERA calculations?

In baseball scoring, innings are expressed in thirds. The digit after the decimal represents outs recorded: .1 = one out (one-third inning), .2 = two outs (two-thirds inning). This calculator converts those fractions automatically before computing ERA.

What is the difference between ERA and WHIP?

ERA measures earned runs allowed per nine innings, while WHIP (Walks + Hits per Inning Pitched) measures baserunners allowed per inning. Both are key pitching metrics but capture different aspects of performance.

Why do some pitchers show an ERA of 0.00 or INF?

A 0.00 ERA means no earned runs have been allowed. An infinite ERA can appear when a pitcher allows earned runs without recording any outs. This calculator shows "—" for zero innings to avoid a division-by-zero error.

Does ERA include unearned runs?

No. Unearned runs — those that score due to fielding errors — are excluded from ERA. Only runs the pitcher is directly responsible for count toward the calculation.

Baseball ERA Calculator

Enter earned runs and innings pitched to instantly calculate a baseball pitcher's ERA.

Pitcher Stats

Pitcher Name (optional)

Earned Runs (ER)

Innings Pitched (IP)

Use .1 for 1 out, .2 for 2 outs (e.g., 6.2 = 6⅔ innings)

Quick Examples

Enter stats on the left to see ERA

ERA Formula

ERA = (Earned Runs ÷ Innings Pitched) × 9

Partial innings use baseball's scoring convention: .1 = ⅓ inning, .2 = ⅔ inning. For example, 7.2 IP converts to 7 + (2/3) = 7.667 true innings.

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Summary

The Earned Run Average (ERA) is the primary statistic used to measure a pitcher's effectiveness. It represents the average number of earned runs a pitcher allows per nine innings pitched. A lower ERA indicates better performance — elite pitchers typically post ERAs below 3.00, while an ERA above 5.00 is considered poor at the major league level.

How it works

Enter the total number of earned runs allowed by the pitcher.
Enter the total innings pitched, including partial innings (e.g., 6.2 for six and two-thirds innings).
The calculator applies the official formula: ERA = (Earned Runs ÷ Innings Pitched) × 9.
Partial innings are automatically converted — .1 equals one-third of an inning, .2 equals two-thirds.
Your result is displayed instantly and color-coded by quality tier.

Use cases

Evaluate a starting pitcher's season performance.
Compare ERA across multiple pitchers on your fantasy baseball roster.
Track a relief pitcher's effectiveness over a stretch of outings.
Calculate mid-season ERA to project end-of-year statistics.
Analyze historical pitching records from boxscores.
Coach youth or amateur baseball and monitor pitching staff ERAs.

Frequently Asked Questions

Last updated: 2026-05-29 · Reviewed by Nham Vu