Home Run to Fly Ball rate (HR/FB) is the ratio of home runs a player hits out of their total number of fly balls. While a player’s raw total of home runs will tell you something, their HR/FB ratio can be useful in providing context about how sustainable their power is.

For example, say there is a player that typically hits around 30 home runs a season, but last year they only hit 20. As a fan, you want to know why that drop in production happened and if there’s something to worry about. Was the player still hitting the same about of fly balls but with a lower HR/FB rate? This could imply that the player lost a touch off their power, which could be a result of an injury or the tell-tale sign of an aging slugger. Or did the player still have the same HR/FB rate, but he was hitting fewer fly balls? If a player goes from hitting fly balls to ground balls, that could be attributed to contact issues. But if the player started to hit more line drives, they may have sacrificed some home runs for more doubles and overall hits.


Please note that the following chart is meant as an estimate, and that league-average HR/FB rate varies on a year-by-year basis. To see the league-average HR/FB rate for every year from 2002 to the present, check the FanGraphs leaderboards.

Rating HR/FB
Excellent 20.0%
Great 15.0%
Above Average 12.5%
Average 9.5%
Below Average 7.5%
Poor 5.0%
Awful 1.0%

Good home run hitters typically have HR/FB ratios anywhere from 15-20%, while weaker players have ratios that range as low as 1%.

Things to Remember:

● Different parks can result in different HR/FB numbers for hitters. For example, a right handed hitter will have a higher HR/FB rate in Fenway Park than in PETCO Park.

● Use this statistic in conjunction with other batted ball statistics. It’s useful, but mostly when put in the context of a player’s overall hitting profile.

● Though more rare, home runs can also come off of line drives.

● This statistic is more important for evaluating pitchers than for hitters.

Links for Further Reading:

HR/FB Park Factors – Hardball Times

Steve is the editor-in-chief of DRaysBay and the keeper of the FanGraphs Library. You can follow him on Twitter at @steveslow.

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Ben Bonoma Recent comment authors
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Ben Bonoma
Ben Bonoma

Hi Steve,

Is there a source of data that documents various outcomes, or a data source where this information can be derived? I am specifically looking for such data points as “How many doubles resulted in a RBI vs. How many singles resulted in a RBI”, and “How many bases were stolen after a single verse a double” as examples.

As with most readers of this site, I love consuming baseball analytics but I have yet to come across these type of numbers. Also, I love reading Fangraphs and the insight it provides.

Thanks for your writing, love the articles.