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OBP: not making outs is the whole job

A team gets 27 outs per game. What's the one thing a hitter can do with every plate appearance?

Not make one of those outs. That reframe — outs are the scarce resource, not hits — is the founding insight of modern baseball analysis. On-base percentage measures exactly it: of all your trips to the plate, how often did you avoid an out?

The walk finally counts

OBP counts hits, walks, and hit-by-pitches, divided by (nearly) all plate appearances. A walk and a single aren't equal — the single advances runners further — but both keep the inning alive, and both beat an out by a mile. AVG's blind spot is OBP's headline feature.

Rule of thumb: OBP runs about 60–70 points above AVG for a normal hitter. A gap much bigger than that means elite plate discipline; a gap under 30 points means the hitter never walks — and pitchers will eventually stop throwing him strikes.

The formula (optional — skippable)

OBP = (H + BB + HBP) ÷ (AB + BB + HBP + SF)

How this stat lies to you

  • It treats a walk exactly like a single — slightly too generous to walks.
  • It says nothing about power: a .380 OBP slap hitter and a .380 OBP slugger look identical.
  • Intentional walks inflate it for feared hitters (a compliment, but not a skill event).

Check yourself

1. Why do analysts prize OBP over AVG?

2. A hitter has AVG .270 and OBP .275. What do you instantly know?