About the ERA Calculator
Earned run average (ERA): earned runs allowed per nine innings pitched.
Also known as: earned run average, era baseball, pitcher era.
How to use this calculator
- Enter earned runs, innings pitched, innings per game.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
ERA = earned runs ÷ innings pitched × 9
Worked example
Using the values pre-filled in the calculator above:
- Earned runs = 42
- Innings pitched = 118.2
- Innings per game = 9
the calculator returns:
- ERA: 3.19
- Innings pitched: 118.67
- Earned runs per inning: 0.354