On-Base Percentage Calculator

Calculate on-base percentage (OBP) from hits, walks, hit-by-pitch, and at-bats.

What On-Base Percentage Measures

On-base percentage (OBP) measures how often a batter reaches base per plate appearance, counting hits, walks, and being hit by a pitch. Unlike batting average, which only credits hits, OBP rewards a hitter's ability to avoid making outs and get on base by any means.

The Formula

  • OBP = (H + BB + HBP) / (AB + BB + HBP + SF)
  • H = Hits, BB = Walks (Bases on Balls)
  • HBP = Hit By Pitch, SF = Sacrifice Flies
  • AB = At Bats

Why OBP Beats Batting Average

Batting average ignores walks and hit-by-pitches, so two players with the same average can have very different real value. A patient hitter who draws many walks reaches base more often and creates more scoring opportunities. Because avoiding outs is the most important thing a hitter can do, OBP correlates more strongly with run scoring than batting average does.

Typical OBP Ranges

  • .400+ - Excellent (Elite)
  • .360-.399 - Great
  • .330-.359 - Above Average
  • .320-.329 - Average
  • .310-.319 - Below Average
  • Below .310 - Poor