wOBA: OBP with correct prices
What if OBP knew that a homer beats a walk?
OBP's flaw is the opposite of AVG's: it counts reaching base but pretends all ways are equal. Weighted On-Base Average fixes that by paying each event its real run value, then rescaling so the result reads like an OBP (league average ≈ .318, great ≈ .400).
One number, honest weights
That's the whole trick: it's OBP where a walk earns ~0.69, a single ~0.88, a double ~1.24, and a homer ~2.05 (the run values, rescaled). Nothing exotic — just correct arithmetic over things you already understand.
wOBA is the best 'how good is this hitter, in one rate stat' number in mainstream use. It's also the exact scale Statcast's xwOBA lives on (Level 4), so learning it now pays twice.
The formula (optional — skippable)
wOBA = (0.69·BB + 0.72·HBP + 0.88·1B + 1.24·2B + 1.57·3B + 2.05·HR) ÷ PA*
Weights drift slightly by season; PA* excludes IBB. Don't memorize — understand that the coefficients are run values.
How this stat lies to you
- No park/league adjustment — that's wRC+'s job (next lesson).
- Same-scale-as-OBP is a design courtesy, not equality: .350 wOBA ≠ .350 OBP in meaning.
- It's still offense only — no baserunning, no defense.
Check yourself
1. wOBA improves on OBP by…
2. League-average wOBA is roughly…