What is a Hit By Pitch? Definition, Formula, and Example
A hit by pitch (HBP) awards the batter first base when a pitch strikes him without his swinging at it, boosting on-base percentage while leaving batting average untouched.
What Is a Hit By Pitch in Baseball?
A hit by pitch (HBP) occurs when a pitched ball touches the batter — his body, clothing, or protective gear — and he is awarded first base as a result. The batter must not have swung at the pitch and must have made an honest effort to avoid it; if the umpire rules he leaned into the ball or made no attempt to get out of the way, the pitch is called a ball instead and no base is awarded. A hit by pitch is functionally a free baserunner: it advances the hitter exactly like a walk, without requiring him to put the ball in play or draw four balls.
How a Hit By Pitch Is Recorded and Measured
HBP is a discrete counting stat — one is logged each time the umpire awards the base. Its statistical weight comes from how it flows into the rate stats. Critically, a hit by pitch is not an at-bat, so it never appears in the batting-average denominator, but it is a plate appearance and counts as a time on base:
OBP = (H + BB + HBP) / (AB + BB + HBP + SF)
That placement means HBP inflates on-base percentage without touching batting average. It also carries a positive coefficient in wOBA, valued almost identically to an unintentional walk because the outcome — a runner on first, no out — is the same.
Worked Example: Anthony Rizzo
Anthony Rizzo built a career out of crowding the plate. In 2015 he was hit 30 times, leading the National League, and he led the NL in HBP for three straight seasons. Consider a simplified line: 550 at-bats, 160 hits, 60 walks, 30 HBP, 5 sacrifice flies.
Batting average = 160 / 550 = .291
OBP = (160 + 60 + 30) / (550 + 60 + 30 + 5) = 250 / 645 = .388
Those 30 hit-by-pitches lift his OBP by roughly 40 points versus a player who took the same trips but never wore one. For a leadoff-caliber bat, that is a full extra baserunner every five or six games.
Why Hit By Pitch Matters
Getting plunked is a genuine, if painful, skill — hitters like Rizzo, Brandon Guyer, and Starling Marte turn plate coverage and fearlessness into free bases. Front offices fold HBP into on-base metrics that drive lineup construction, and because it feeds OBP and wOBA, it quietly raises a player's overall value. In OBP fantasy leagues it is scored dollars; in standard 5×5 leagues it is invisible, which makes plate-crowding grinders underrated there.
Limitations and Common Misconceptions
HBP does not count as a hit, so it never helps batting average — a common fan error. It is also partly involuntary: some HBP totals reflect pitchers with poor command or intentional retaliation rather than batter skill, so the stat blends the hitter's approach with luck. And a high HBP total carries injury risk that the raw number hides. Read it as a small, real bump to on-base ability, not a marquee stat.
Related Terms
In Legends Deck: A card's Plate Discipline and On-Base ratings absorb hit-by-pitch tendency, so a plate-crowder like Rizzo grades higher on-base than his batting average alone suggests. In-game, hitters with elevated HBP profiles draw more free passes against wild pitchers — turning a control lapse on the mound into an extra runner for you, exactly as it plays out on the field.