baseball Baseball is a bat-and-ball sport played between two teams of nine players each, taking turns batting and fielding. The game occurs over the course of several plays, with each play generally beginning when a player on the fielding t ...

, the

strikeout In baseball or softball, a strikeout (or strike-out) occurs when a batter accumulates three strikes during a time at bat. It usually means that the batter is out. A strikeout is a statistic recorded for both pitchers and batters, and is den ...

is a

statistic A statistic (singular) or sample statistic is any quantity computed from values in a sample which is considered for a statistical purpose. Statistical purposes include estimating a population parameter, describing a sample, or evaluating a hypo ...

used to evaluate

pitcher In baseball, the pitcher is the player who throws ("pitches") the baseball from the pitcher's mound toward the catcher to begin each play, with the goal of retiring a batter, who attempts to either make contact with the pitched ball or dr ...

s. A pitcher earns a strikeout when he puts out the batter he is facing by throwing a ball through the strike zone, "defined as that area over homeplate ''(sic)'' 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 kneecap", which is not put in play. Strikeouts are awarded in four situations: if the batter is put out on a third strike caught by the catcher (to " strike out swinging" or " strike out looking"); if the pitcher throws a third strike which is not caught with fewer than two outs; if the batter becomes a baserunner on an uncaught third strike; or if the batter bunts the ball into foul territory with two strikes.

Major League Baseball Major League Baseball (MLB) is a professional baseball organization and the oldest major professional sports league in the world. MLB is composed of 30 total teams, divided equally between the National League (NL) and the American League (A ...

recognizes the player or players in each league with the most strikeouts each season. Jim Devlin led the

National League The National League of Professional Baseball Clubs, known simply as the National League (NL), is the older of two leagues constituting Major League Baseball (MLB) in the United States and Canada, and the world's oldest extant professional team s ...

in its inaugural season of 1876; he threw 122 strikeouts for the Louisville Grays. The American League's first winner was

Hall of Fame A hall, wall, or walk of fame is a list of individuals, achievements, or other entities, usually chosen by a group of electors, to mark their excellence or fame in their field. In some cases, these halls of fame consist of actual halls or muse ...

pitcher

Cy Young Denton True "Cy" Young (March 29, 1867 – November 4, 1955) was an American Major League Baseball (MLB) pitcher. Born in Gilmore, Ohio, he worked on his family's farm as a youth before starting his professional baseball career. Young entered th ...

, who captured the

American League Triple Crown In baseball, a player earns a Triple Crown when he leads a league in three specific statistical categories in the same season. The term "Triple Crown" generally refers to the batting achievement of leading a league in batting average, home runs, ...

in 1901 by striking out 158 batters, along with leading the league in wins and

earned run average In baseball statistics, earned run average (ERA) is the average of earned runs allowed by a pitcher per nine innings pitched (i.e. the traditional length of a game). It is determined by dividing the number of earned runs allowed by the numb ...

. Walter Johnson led the American League in strikeouts twelve times during his Hall of Fame career, most among all players. He is followed by Nolan Ryan, who captured eleven titles between both leagues (nine in the American League and two in the National League). Randy Johnson won nine strikeout titles, five coming with the Arizona Diamondbacks. Three players have won seven strikeout championships: Dazzy Vance, who leads the National League;

Bob Feller Robert William Andrew Feller (November 3, 1918 – December 15, 2010), nicknamed "the Heater from Van Meter", "Bullet Bob", and "Rapid Robert", was an American baseball pitcher who played 18 seasons in Major League Baseball (MLB) for the Clevel ...

; and Lefty Grove. Grover Cleveland Alexander and

Rube Waddell George Edward Waddell (October 13, 1876 – April 1, 1914) was an American pitcher in Major League Baseball (MLB). A left-hander, he played for 13 years, with the Louisville Colonels, Pittsburgh Pirates, and Chicago Orphans in the National ...

led their league six times, and five-time winners include

Steve Carlton Steven Norman Carlton (born December 22, 1944) is an American former professional baseball player. He played in Major League Baseball as a left-handed pitcher for six different teams from 1965 to 1988, most notably as a member of the Philadelph ...

Roger Clemens William Roger Clemens (born August 4, 1962), nicknamed "Rocket", is an American former professional baseball pitcher who played 24 seasons in Major League Baseball (MLB), primarily with the Boston Red Sox. Clemens was one of the most dominant pi ...

Sam McDowell Samuel Edward Thomas McDowell (born September 21, 1942), is an American former professional baseball player. He played in Major League Baseball as a starting pitcher from 1961 to 1975, most notably for the Cleveland Indians. A six-time All-Star, ...

, Christy Mathewson,

Amos Rusie Amos Wilson Rusie (May 30, 1871 – December 6, 1942), nicknamed "The Hoosier Thunderbolt", was an American right-handed pitcher in Major League Baseball during the late 19th century. He had a 10-season career in the National League (NL), w ...

, and Tom Seaver. There are several players with a claim to the single-season strikeout record. Among recognized major leagues,

Matt Kilroy Matthew Aloysius "Matches" Kilroy (June 21, 1866 – March 2, 1940) was an American left-handed pitcher in Major League Baseball. In 1886, he had 513 strikeouts, which remains the MLB single-season record. Early life Kilroy was born in Philadelp ...

accumulated the highest single-season total, with 513 strikeouts for the

Baltimore Orioles The Baltimore Orioles are an American professional baseball team based in Baltimore. The Orioles compete in Major League Baseball (MLB) as a member club of the American League (AL) East division. As one of the American League's eight charter ...

of the

American Association American Association may refer to: Baseball * American Association (1882–1891), a major league active from 1882 to 1891 * American Association (1902–1997), a minor league active from 1902 to 1962 and 1969 to 1997 * American Association of Profe ...

in 1886. However, his name does not appear on Major League Baseball's single-season leaders list, since the American Association was independent of the constituent leagues that currently make up Major League Baseball. Several other players with high totals, including 1886 American Association runner-up Toad Ramsey (499) and 1884 Union Association leader Hugh Daily (483), do not appear either. In the National League, Charles "Old Hoss" Radbourn struck out 441 batters for the Providence Grays; however, the Providence franchise folded after the 1885 season and has no successor. Therefore, Major League Baseball recognizes his runner-up from that season,

Charlie Buffinton Charles "Charlie" G. Buffinton (June 14, 1861 – September 23, 1907) was an American right-handed pitcher in Major League Baseball from 1882 to 1892. One of the workhorse pitchers of the 1880s, he won 20 games seven times and his 1,700 career ...

, as the record-holder with 417 strikeouts. In the American League, Ryan leads with 383 strikeouts in 1973. The largest margin of victory for a champion is 156 strikeouts, achieved in 1883 when

Tim Keefe Timothy John Keefe (January 1, 1857 – April 23, 1933), nicknamed "Smiling Tim" and "Sir Timothy", was an American Major League Baseball pitcher. He stood tall and weighed . He was one of the most dominating pitchers of the 19th century and po ...

of the American Association's

New York Metropolitans The Metropolitan Club (New York Metropolitans or the Mets) was a 19th-century professional baseball team that played in New York City from 1880 to 1887. (The ''New York Metropolitan Baseball Club'' was the name chosen in 1961 for the New Yor ...

posted 359 against Bobby Mathews' 203. The National League's largest margin was achieved in 1999, when Randy Johnson struck out 143 more batters than Kevin Brown. Ryan's 1973 margin of 125 strikeouts over Bert Blyleven is the best American League victory. Although ties for the championship are rare, they have occurred; Claude Passeau and

Bucky Walters William Henry "Bucky" Walters (April 19, 1909 – April 20, 1991) was an American professional baseball pitcher who played in Major League Baseball from 1931 to 1950. He was a six-time All-Star and the 1939 National League Most Valuable Player. ...

each struck out 137 National League batters in 1939, and

Tex Hughson Cecil Carlton Hughson, (February 9, 1916 – August 6, 1993) was a Major League Baseball starting pitcher who played his entire career in the American League with the Boston Red Sox (1941–44, 1946–49). He batted and threw right-handed. A nat ...

and

Bobo Newsom Louis Norman "Bobo" Newsom (August 11, 1907 – December 7, 1962) was an American starting pitcher in Major League Baseball. Also known as "Buck", Newsom played for nine of the 16 then-existing big-league teams from 1929 through 1953 over all o ...

tied in the American League with 113 strikeouts each in 1942. Their total is the lowest number of strikeouts accumulated to lead a league in Major League Baseball history (although Jacob deGrom only struck out 104 National League batters in 2020, the season was shortened by a pandemic to 60 game, or 37.04% of a regular season; had that season run a full 162 games, that would have been a net of 281 strikeouts).

Key

National League

American League

Other major leagues

Footnotes

*Recognized "major leagues" include the current

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...

and

s and several defunct leagues—the

, the Federal League, the

Players' League The Players' National League of Professional Base Ball Clubs, popularly known as the Players' League (PL), was a short-lived but star-studded professional American baseball league of the 19th century. The PL was formed by the Brotherhood of Prof ...

, and the Union Association. *In

baseball scorekeeping Baseball scorekeeping is the practice of recording the details of a baseball game as it unfolds. Professional baseball leagues hire official scorers to keep an official record of each game (from which a box score can be generated), but many fans ...

, "K" is the traditional notation for the strikeout. *In 1939, Claude Passeau played the entire season for the

Cincinnati Reds The Cincinnati Reds are an American professional baseball team based in Cincinnati. They compete in Major League Baseball (MLB) as a member club of the National League (NL) National League Central, Central division and were a charter member of ...

, while co-leader

was traded from the

Philadelphia Phillies The Philadelphia Phillies are an American professional baseball team based in Philadelphia. They compete in Major League Baseball (MLB) as a member of the National League (NL) National League East, East division. Since 2004, the team's home sta ...

to the

Chicago Cubs The Chicago Cubs are an American professional baseball team based in Chicago. The Cubs compete in Major League Baseball (MLB) as part of the National League (NL) Central division. The club plays its home games at Wrigley Field, which is locate ...

mid-season.

References

;General * * ;Inline citations {{featured list Strikeout champions

Strikeout In baseball or softball, a strikeout (or strike-out) occurs when a batter accumulates three strikes during a time at bat. It usually means that the batter is out. A strikeout is a statistic recorded for both pitchers and batters, and is den ...

Striking out the sides