IVBInches
Induced vertical break
Vertical movement relative to a gravity-only pitch. Positive IVB means less drop; it does not require an upward trajectory.
Try the interactive explanationThe metric library
A number is only
the beginning.
What it measures. What it leaves out. A few useful ways to read the game.
mphMiles per hour
Velocity
Pitch speed at release. The movement dashboard shows each pitcher’s season mean for four-seam fastballs.
MLB’s definitionWhiff%Percent of swings
Whiff rate
How often a swing misses: misses divided by swings. Taken pitches are outside this denominator.
See the source leaderboardUsage%Percent of pitches
Pitch usage
The share of a pitcher’s pitches thrown as a given type. Our qualifying table can omit less-used pitches, so the displayed shares may not sum to 100%.
Explore pitcher statisticsK%Percent of plate appearances
Strikeout rate
Strikeouts divided by plate appearances. In the pitch-type table, this describes plate appearances ending on that pitch type.
MLB’s definitionRead the label, too.
Aggregate identifies the 2025 season statistics. Simulated identifies the teaching model, where you control one variable. The illustration in the footer is AI-generated; the pitch calculations are deterministic.