The Strike Zone : A History of Official Strike Zone Rules

Major League Baseball defines, in the most recent issue of its official rule book (Definition of Terms - 2.00), a baseball strike zone with the following description:

The STRIKE ZONE is that area over home plate the upper limit of which is a horizontal line at the midpoint between the top of the shoulders and the top of the uniform pants, and the lower level is a line at the hollow beneath the knee cap. The Strike Zone shall be determined from the batter's stance as the batter is prepared to swing at a pitched ball.

Baseball Almanac is pleased to present a comprehensive look at the history of the strike zone. Included below are official rules, definitions, clarifications, and official statements made about the strike zone over the course of baseball history.

Baseball Almanac Top Quote

"The game is all about control of the seventeen inch triangle. Hitters who force pitchers to stay in the strike zone are productive and pitchers who take hitters out of the strike zone are dominate." - Oakland Athletics General Manager Billy Beane on ESPN.com (Peter Gammons, 09/08, 'Contenders' flaws add intriguing plot twists, like any great drama', Source)

The Strike Zone

The Strike Zone by Baseball Almanac

A Chronological Examination of the Official Rules

1996

The Strike Zone is expanded on the lower end, moving from the top of the knees to the bottom of the knees (bottom has been identified as the hollow beneath the kneecap).

1988

The Strike Zone is that area over home plate the upper limit of which is a horizontal line at the midpoint between the top of the shoulders and the top of the uniform pants, and the lower level is a line at the top of the knees. The Strike Zone shall be determined from the batter's stance as the batter is prepared to swing at a pitched ball.

1969

The Strike Zone is that space over home plate which is between the batter's armpits and the top of his knees when he assumes a natural stance. The umpire shall determine the Strike Zone according to the batter's usual stance when he swings at a pitch.

1963

The Strike Zone is that space over home plate which is between the top of the batter's shoulders and his knees when he assumes his natural stance. The umpire shall determine the Strike Zone according to the batter's usual stance when he swings at a pitch.

1957

A strike is a legal pitch when so called by the umpire which:

(a) is struck at by the batter and is missed;
(b) enters the Strike Zone in flight and is not struck at;
(c) is fouled by the batter when he has less than two strikes at it;
(d) is bunted foul;
(e) touches the batter as he strikes at it;
(f) touches the batter in flight in the Strike Zone; or
(g) becomes a foul tip. Note:
(f) was added to the former rule and definition.

1950

The Strike Zone is that space over home plate which is between the batter's armpits and the top of his knees when he assumes his natural stance.

1910

With the bases unoccupied, any ball delivered by the pitcher while either foot is not in contact with the pitcher's plate shall be called a ball by the umpire.

1907

A fairly delivered ball is a ball pitched or thrown to the bat by the pitcher while standing in his position and facing the batsman that passes over any portion of the home base, before touching the ground, not lower than the batsman's knee, nor higher than his shoulder. For every such fairly delivered ball, the umpire shall call one strike.

An unfairly delivered ball is a ball delivered to the bat by the pitcher while standing in his position and facing the batsman that does not pass over any portion of the home base between the batsman's shoulder and knees, or that touches the ground before passing home base, unless struck at by the batsman. For every unfairly delivered ball the umpire shall call one ball.

1901

A foul hit ball not caught on the fly is a strike unless two strikes have already been called. Adopted by National League in 1901 and the American League in 1903.

1899

A foul tip by the batter, caught by the catcher while standing within the lines of his position is a strike.

1894

A strike is called when the batter makes a foul hit, other than a foul tip, while attempting a bunt hit that falls or rolls upon foul ground between home base and first or third bases.

1887

The batter can no longer call for a 'high' or 'low' pitch.

A (strike) is defined as a pitch that 'passes over home plate not lower than the batsman's knee, nor higher than his shoulders.

1876

The batsman, on taking his position, must call for a 'high,' 'low,' or 'fair' pitch, and the umpire shall notify the pitcher to deliver the ball as required; such a call cannot be changed after the first pitch is delivered.

High - pitches over the plate between the batter's waist and shoulders

Low - pitches over the plate between the batter's waist and at least one foot from the ground.

Fair - pitches over the plate between the batter's shoulders and at least one foot from the ground.

A Chronological Examination of the Official Strike Zone Rules
baseball almanac flat baseball

baseball almanac fast facts

QuesTec's Umpire Information System is based on the military's missile tracking system and uses cameras, computers, and strike zone software for tracking strikes. In 2003 it was in operation in ten ballparks (Anaheim, Arizona, Atlanta, Boston, Cleveland, Kansas City, Milwaukee, New York [N.L.], San Francisco & Tampa Bay) and at the game's completion, a CD-ROM with every pitch is given to the umpire — and Major League Baseball. The system could actually "tell" the umpire if the pitch was in the strike zone while it was taking place. Umpires, players, executives & fans all feel differently about the system and we invite you to share your opinion on Baseball Fever.

Did you know that Ted Williams, who many historians / experts believe was the best hitter in the history of Major League Baseball, once made the following insightful comment about the strike zone:

"The batter has three strike zones: his own, the opposing pitcher's, and the umpire's. The umpire's zone is defined by the rule book, but it's also more importantly defined by the way the umpire works. A good umpire is consistent so you can learn his strike zone. The batter has a strike zone in which he considers the pitch the right one to hit. The pitchers have zones where they are most effective. Once you know the pitcher and his zone you can get set for a particular pitch.

Davey Johnson (1999) once summed up all the strike zone rule changes in a single statement, "It's always been the job of the hitter and pitcher to recognize the strike zone for that particular night, whether it is high or wide, and adjust accordingly. It's been like that for like two-hundred years."