Real MLB pitches. Real strike zones. Call balls and strikes and see how you stack up against the actual umpire behind the plate.
Built on real Statcast pitch data from Baseball Savant and the MLB Stats API.
Every pitch is sourced from Baseball Savant. Real coordinates, real spin rates, real umpires — no simulations.
Uses MLB's Automated Ball-Strike system rules. If any part of the ball touches the rulebook zone, it's a strike.
Track your accuracy over time. See which pitch types you struggle with and where in the zone you're weakest.
Play only the pitches the umpire got wrong. Perfect for reliving the moments that made you yell at the TV.
Search for every game called by a specific umpire this season. Find out if Laz Diaz really is as bad as you think.
10 blown calls from yesterday's games. Same pitches for everyone. Share your score and challenge your friends.
Watch the ball fly from the pitcher's hand toward the plate in real perspective. The ball's speed, break, and trajectory are all derived from real Statcast measurements.
Before the zone is revealed, tap Ball or Strike. The measurement bar showing the batter's knee and letter heights fades out as the ball arrives — no cheating.
The rulebook strike zone appears with the ball at its exact coordinates. Borderline pitches earn bonus points. You'll also see whether the actual umpire got it right.
At the end of each game, your accuracy is compared directly against the umpire's. Some MLB umps sit around 94% accuracy. Can you beat them?
10 random borderline pitches from recent games. Quick, addictive, and great for building your eye.
FREE10 blown calls from yesterday. Same pitches for every player worldwide. New challenge every day.
FREEPick any real MLB game. Call every pitch in order with live count, score, and inning data.
PROFilter any game to only the pitches the umpire missed. How many can you spot correctly?
PROEvery pitch coordinate, spin rate, and velocity comes directly from official sources — the same data that drives ABS challenges during real games.
Free to download. Arcade and Daily Challenge always free.
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