baseball statistics Baseball statistics play an important role in evaluating the progress of a player or team. Since the flow of a baseball game has natural breaks to it, and normally players act individually rather than performing in clusters, the sport lends itsel ...

, strikeout-to-walk ratio (K/BB) is a measure of a

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 draw ...

's ability to control pitches, calculated as

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 deno ...

s divided by

bases on balls A base on balls (BB), also known as a walk, occurs in baseball when a batter receives four pitches that the umpire calls '' balls'', and is in turn awarded first base without the possibility of being called out. The base on balls is defined in Se ...

. A

hit by pitch In baseball, hit by pitch (HBP) is an event in which a batter or his clothing or equipment (other than his bat) is struck directly by a pitch from the pitcher; the batter is called a hit batsman (HB). A hit batsman is awarded first base, provided ...

is not counted statistically as a walk, and therefore not counted in the strikeout-to-walk ratio. The inverse of this calculation is the related statistic for hitters,

walk-to-strikeout ratio In baseball statistics, walk-to-strikeout ratio (BB/K) is a measure of a hitter's plate discipline and knowledge of the strike zone. Generally, a hitter with a good walk-to-strikeout ratio must exhibit enough patience at the plate to refrain from ...

(BB/K).

Leaders

Through 2022, the all-time career leaders among starting pitchers were

Chris Sale Christopher Allen Sale (born March 30, 1989) is an American professional baseball pitcher for the Boston Red Sox of Major League Baseball (MLB). He previously played in MLB for the Chicago White Sox, with whom he made his major league debut ...

(5.3333), Jacob de Grom (5.3036), and

Tommy Bond Thomas Ross Bond (September 16, 1926 – September 24, 2005) was an American actor, director, producer and writer. He was best known for his work as a child actor for two nonconsecutive periods on ''Our Gang'' (''Little Rascals'') comedies (fir ...

(5.0363). Through May 22, 2019, the all-time career leaders among relievers were

Koji Uehara is a Japanese former professional baseball pitcher. He previously played for the Yomiuri Giants of Nippon Professional Baseball (NPB), as well as the Baltimore Orioles, Texas Rangers, Boston Red Sox, and Chicago Cubs of Major League Baseball (M ...

(7.94),

Sean Doolittle Sean Robert Doolittle (born September 26, 1986) is an American professional baseball pitcher in the Washington Nationals organization. He has played in Major League Baseball (MLB) for the Oakland Athletics, Cincinnati Reds, Seattle Mariners a ...

(6.41), and

Roberto Osuna Roberto Osuna Quintero Jr. (born February 7, 1995) is a Mexican professional baseball pitcher for the Fukuoka SoftBank Hawks of Nippon Professional Baseball (NPB). He has played in Major League Baseball (MLB) for the Toronto Blue Jays and Hous ...

(6.33).

The player with the highest single regular season K/BB ratio through 2022 was

Minnesota Twins The Minnesota Twins are an American professional baseball team based in Minneapolis. The Twins compete in Major League Baseball (MLB) as a member club of the American League (AL) Central Division. The team is named after the Twin Cities area w ...

pitcher

Phil Hughes Philip Joseph Hughes (born June 24, 1986) is an American former professional baseball pitcher. He has played in Major League Baseball (MLB) for the New York Yankees, Minnesota Twins, and San Diego Padres from 2007 through 2018. He stands tal ...

in 2014, with a ratio of 11.625 (186 strikeouts and 16 walks). He is followed by

Bret Saberhagen Bret William Saberhagen (; born April 11, 1964) is an American former professional baseball right-handed starting pitcher. He played in Major League Baseball (MLB) for the Kansas City Royals, New York Mets, Colorado Rockies, and Boston Red Sox fro ...

(11.00 in 1994) and

Cliff Lee Clifton Phifer Lee (born August 30, 1978) is an American former professional baseball starting pitcher who played for 13 seasons in Major League Baseball (MLB). Between 2002 and 2014 he played for four teams, most notably the Philadelphia Philli ...

(10.28 in 2010). In 2016,

Clayton Kershaw Clayton Edward Kershaw (born March 19, 1988) is an American professional baseball pitcher for the Los Angeles Dodgers of Major League Baseball (MLB) . He has played for the Dodgers for the entirety of his MLB career. A left-handed starting p ...

struck out 172 batters while walking only 11 for a ratio of 15.6; however he pitched only 149 innings, not enough to qualify for the record. A pitcher who possesses a great K/BB ratio is usually a dominant

power pitcher Power pitcher is a term in baseball for a pitcher who relies on pitch velocity at the expense of accuracy. Power pitchers usually record a high number of strikeouts, and statistics such as strikeouts per 9 innings pitched are common measures of ...

, such as

Randy Johnson Randall David Johnson (born September 10, 1963), nicknamed "The Big Unit", is an American photographer and former professional baseball pitcher who played 22 seasons in Major League Baseball (1988–2009) for six teams, primarily the Seattle M ...

Pedro Martínez Pedro Jaime Martínez (born October 25, 1971) is a Dominican-American former professional baseball starting pitcher, who played in Major League Baseball (MLB) from to , for five teams—most notably the Boston Red Sox from to . At the time o ...

Curt Schilling Curtis Montague Schilling (born November 14, 1966) is an American former Major League Baseball right-handed pitcher who is a commentator for conservative media outlet BlazeTV. He helped lead the Philadelphia Phillies to a World Series appearance ...

, or

Mariano Rivera Mariano Rivera (born November 29, 1969) is a Panamanian-American former professional baseball pitcher who played 19 seasons in Major League Baseball (MLB) for the New York Yankees, from 1995 to 2013. Nicknamed "Mo" and "Sandman", he spent most ...

. However, in 2005,

starting pitcher In baseball (hardball or softball), a starting pitcher or starter is the first pitcher in the game for each team. A pitcher is credited with a game started if they throw the first pitch to the opponent's first batter of a game. Starting pit ...

Carlos Silva easily led the major leagues in K/BB ratio with 7.89:1, despite striking out only 71 batters over 188⅓ innings pitched; he walked only nine batters.

References

Pitching statistics Statistical ratios {{Baseball-stub