Academy Courses

Strike Zone Defined

Strike Zone

The strike zone is a three-dimensional area over home plate where the pitcher attempts to deliver the pitch and the batter is taught to swing and hit the ball. The width (17”) and depth is that of home plate. The top and bottom of the strike zone is determined by the height and stance of the hitter.

The top of the strike zone is the midpoint between the top of the shoulders and the top of the uniform pants. The bottom of the strike zone is the hollow beneath the kneecap. The height of the strike zone is determined by the stance of the batter as he begins to swing at a pitched ball.

strike zone width

If a legal pitch passes through any point of the strike zone, it is called a strike. Any pitch that does not pass through any point of the strike zone and the umpire judges that the batter did not attempt to hit the pitch, is called a ball.

A baseball is approximately three inches in diameter (2.944”) and home plate is 17” wide. Since the rulebook specifies that a legal pitch is a strike “if any part of the ball passes through any part of the strike zone.” So, as the diagram below shows, the strike zone is effectively 23” wide.

Good Ball/Strike Positioning Has Other Benefits: [Umpire Tip

GThis expert Umpire Tip explains the necessity for the home plate umpire to “get into the slot” to properly see pitches. Poor positioning leads to poor umpiring – don’t let that happen to you.

Swinging Strike

  • A swinging strike is when the batter attempts to hit a pitch and misses it. The pitch might be outside of the strike zone but since the batter attempted to hit the pitch (swing and miss), he will be charged with a strike.
  • Umpires look for the location of the head of the bat when judging a check swing. If the head of the bat swings past the front edge of home plate, it is usually called a strike. Professional umpires do not judge to see if a batter “breaks his wrist” in a swing attempt. Ultimately, the umpire must decide if the batter made an attempt to hit the ball.

Check Swing

  • If a batter stops his motion of the swing before he is judged to “attempt to hit the pitch,” he will not be charged with a strike. If the umpire judges that he made an “attempt to hit the pitch,” a strike will be called.

Check-Swing Appeal: [Umpire Interpretation 63]

Voluntary Strike: [Umpire Interpretation 64]

What do umpires look for in a check swing?



There are quizzes here, but you do not have access to them. Only registered users can take quizzes.