Sabermetrics Glossary: wOBA
Weighted On-base Average (wOBA) has become one of the most frequently cited “sabermetrics” in baseball over the recent years. Like most of these advanced metrics, it is not nearly as complicated as it seems.
wOBA is similar to on-base percentage (which is just the percent of the time a player reaches base safely). The difference is that the different ways the player reaches base safely have different weights. A home run is worth more than a double, which is worth more than a single, which is worth more than a walk. This makes intuitive sense because of course, you would rather have a player that hits a bunch of doubles and homers over a guy that walks and hits singles. When you are looking at a statistic like on-base percentage, a home run and a walk are worth the same thing.
For full transparency, here is the formula to calculate wOBA (note that the weights do change slightly over time depending on the league environment):
(.7 * BB) + (.7 * HBP) + (.9 * 1B) + (1.3 * 2B) + (1.6 * 3B) + (2.1 * HR)
(AB + BB + SF + HBP)
You can see there that walks and hit by pitches are factored into the equation, so you are getting a pretty full picture of a hitter’s performance when looking at this metric.
Last year’s wOBA leader was Christian Yelich (.442), and here is how the stat generally breaks down:
.400 – Excellent
.370 – Great
.340 – Above Average
.320 – Average
.310 – Below Average
.300 – Poor
.290 – Awful
wOBA is most useful at getting a quick idea about how a player has performed in the past. This gives you more information than just looking at his batting average. For example, in 2019 David Fletcher hit for a very strong .290 batting average, but his lack of extra-base hits gave him a below-average .318 wOBA – he really was not helping your fantasy team in anything but batting average last year.
While the best fantasy baseball players survey various statistics when making decisions, if I had to pick just one statistic that best sums everything up, wOBA would be a real contender.