Baseball Weighted On-Base Average (wOBA)

baseball weighted on base average woba

On-base percentage has been a stat used to evaluate players’ offensive performance for decades in baseball. Weighted-On Base Average (wBOA) is a stat that is somewhat similar, but factors in different types of ways to get on base. Read on to learn more about wOBA in baseball.

Weighted On-Base Average (wOBA)

Weighted On-Base Average (wOBA) is a weighted version of on-base percentage meant to gain a general grasp of what a player’s offensive value is. A weighted on-base average attributes more points to a player's average when they get a hit that earns them extra bases or in some way increases the odds of a run being scored.

wBOA Formula

The formula for calculating wOBA, with the term "factor" indicating the run expectancy of a batting event, is:

(unintentional BB factor x unintentional BB + HBP factor x HBP + 1B factor x 1B + 2B factor x 2B + 3B factor x 3B + HR factor x HR)/(AB + unintentional BB + SF + HBP) = wOBA


In a season where a home run is worth 2.053 on base and a walk is worth 0.73 times on base, a player who goes 1-for-4 with a home run and a walk will have a wOBA of .557. This is because (2.053 + 0.73) / (4 + 1 + 0 + 0) = .557.


What is wOBA in baseball?

Weighted On-Base Average (wOBA) is a weighted version of on-base percentage that factors in the hitter’s ability to hit extra base hits or put their team in scoring position. Extra-base hits will increase a player’s wOBA more than a single-base hit. Much like on-base percentage, walks (BB) also count toward a player’s wOBA, unlike batting average.