Calculate a pitcher's Earned Run Average from innings pitched and earned runs allowed. Enter any partial innings using .1 and .2 notation.
✓ Handles .1 and .2 inning fractional notation
✓ ERA quality rating from Elite to Poor
✓ Formula with step-by-step breakdown
✓ Career ERA context with MLB benchmarks
Enter Pitching StatsFree · Instant
.1 = 1 out, .2 = 2 outs
3.86ERAAbove Average
3 earned runs allowed over 7 innings pitched
3
Earned Runs
7
IP (decimal)
0.78
Games Equiv.
How ERA Is Calculated
ERA normalizes a pitcher's performance to a nine-inning scale, making it easy to compare outings of different lengths.
ERA = (Earned Runs ÷ Innings Pitched) × 9
Innings notation: 6.1 = 6 + 1/3 = 6.333 IP Innings notation: 6.2 = 6 + 2/3 = 6.667 IP
The multiplier of 9 comes from a standard baseball game being nine innings. Multiplying by 9 projects any partial-game performance to a complete-game baseline so you can compare a 3-inning relief appearance with a 7-inning start on equal footing.
Who Uses This Calculator?
Anyone tracking pitching performance, from Little League scorekeeper to fantasy baseball analyst.
Fantasy baseball players
Evaluate a waiver-wire pickup's recent ERA to decide if they are worth adding to your roster.
Coaches and scorekeepers
Quickly compute season ERA after each game without doing the fraction math manually.
Youth league parents
Track your child's pitching stats across the season with an easy-to-use tool.
Sports journalists
Verify ERA figures for articles and verify mid-season projections.
How to Use the Calculator
1
Enter earned runs
Type the number of earned runs the pitcher allowed. Unearned runs (from errors) are not included.
2
Enter innings pitched
Type the IP using standard baseball notation. For 6 innings and 2 outs, enter 6.2, not 6.67.
3
Read the ERA
The result shows ERA to two decimal places with a quality label from Elite to Poor.
4
Check the context stats
Below the ERA you can see the decimal IP conversion and games-equivalent figure for more context.
Example Calculation
Pitcher Marcus Hale throws 6.2 innings and allows 2 earned runs. What is his ERA for that outing?
Innings pitched6.2 (= 6.667 IP)
Earned runs2
ERA = (2 ÷ 6.667) × 9= 2.70
Result: 2.70 ERA (Excellent)
A 2.70 ERA over a full season would place Marcus comfortably in the top tier of major-league starters. Over a single outing it is a strong performance but ERA stabilizes over a larger sample of innings.
Common Mistakes to Avoid
!
Entering 6.33 instead of 6.1
The .1 and .2 in baseball IP notation mean outs, not fractions of 10. Entering 6.33 would be interpreted as 6 full innings plus 3.3 outs, which does not exist. Always use 6.1 for 1 out and 6.2 for 2 outs.
!
Including unearned runs
Only runs that score without the help of a fielding error count as earned. If a run scored solely because of an error, do not include it. Check the official scorer's ruling on your scorecard.
!
Comparing a reliever's ERA to a starter's
Relievers typically post lower ERAs because they pitch fewer innings per appearance and face fresh batters. An ERA of 3.50 for a closer is good but not the same as a 3.50 ERA for a rotation starter.
!
Drawing conclusions from a small sample
ERA based on fewer than 20 innings pitched fluctuates widely. A single bad inning can swing ERA by several points. Trend ERA over a 50-inning minimum before making roster decisions.
MLB Official Rules, Rule 9.16: Earned Runs and Runs Allowed
Defines earned runs, the conditions under which a run is unearned, and how theoretical innings are used to determine earned/unearned status after an error.
2
Baseball Reference: ERA Leaderboards and Career Records
Source for career ERA benchmarks and historical context used in the ERA quality scale on this page.
J
James Kowalski
Baseball statistician and sabermetrics writer, 9 years covering advanced pitching metrics
James reviewed the ERA formula, innings-pitched conversion logic, and quality scale benchmarks on this page. He covers advanced pitching analytics for independent baseball publications.
MLB ERA Quality Scale
Under 2.00
Elite
2.00 – 2.99
Excellent
3.00 – 3.99
Above Average
4.00 – 4.99
Average
5.00 – 5.99
Below Average
6.00+
Poor
Applies to MLB starters. Relievers typically post lower ERAs.
Career ERA Leaders (Min. 1,000 IP)
Ed Walsh1.82
Addie Joss1.89
Walter Johnson2.17
Christy Mathewson2.13
Cy Young2.63
Source: Baseball Reference
Pro Tip
ERA stabilizes around 50 innings pitched. For pitchers with fewer than 20 IP, a single 4-run inning can inflate ERA from 0.00 to over 3.00. Use FIP (Fielding Independent Pitching) alongside ERA for small samples.