HR/9 Calculator (Home Runs per 9 Innings, Baseball)

Calculate HR/9 (home runs per 9 innings) from home runs allowed and innings pitched, or pick K/9, H/9, BB/9 or RA/9 for other pitching stats.

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Home Runs Per 9 Formula

The following formula is used to calculate the home runs per 9 innings for a given number of home runs allowed and innings pitched.

HR / 9 = (HR / IP) \times 9

Variables:

HR/9 is the home runs per 9 innings
HR is the home runs allowed
IP is decimal innings pitched. In baseball notation, .1 and .2 mean one and two outs: 57.2 converts to 57⅔ innings. Select the matching notation in the calculator.

To calculate the home runs per 9 innings, divide the home runs allowed by the innings pitched. Multiply the result by 9 to scale it to a 9-inning game.

What is Home Runs Per 9?

Home Runs Per 9 (HR/9) is a baseball statistic that measures the average number of home runs a pitcher allows per nine innings pitched. This metric is useful for evaluating a pitcher's susceptibility to giving up home runs and is often used in conjunction with other pitching statistics to assess overall performance. A lower HR/9 indicates better performance in preventing home runs.

How to Calculate Home Runs Per 9?

The following steps outline how to calculate the Home Runs Per 9.

First, determine the number of home runs allowed (HR).
Next, determine the number of innings pitched (IP).
Next, calculate the home runs per 9 innings using the formula HR/9 = (HR / IP) * 9.
For the example below, HR/9 = (10 / 90) × 9 = 1 home run per nine innings.
After inserting the values and calculating the result, check your answer with the calculator above.

Example Problem :

Use the following variables as an example problem to test your knowledge.

Home Runs Allowed (HR) = 10

Innings Pitched (IP) = 90