In baseball, the strikeout is a statistic used to evaluate pitchers. 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 recognizes the player or players in each league with the most strikeouts each season. Jim Devlin led the National League in its inaugural season of 1876; he threw 122 strikeouts for the Louisville Grays. The American League's first winner was Hall of Fame pitcher Cy Young, who captured the American League Triple Crown in 1901 by striking out 158 batters, along with leading the league in wins and earned run average. 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; and Lefty Grove. Grover Cleveland Alexander and Rube Waddell led their league six times, and five-time winners include Steve Carlton, Roger Clemens, Sam McDowell, Christy Mathewson, Amos Rusie, and Tom Seaver.
There are several players with a claim to the single-season strikeout record. Among recognized major leagues, Matt Kilroy accumulated the highest single-season total, with 513 strikeouts for the Baltimore Orioles of the American Association 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: for the same reason, several other players with high totals, including 1886 American Association runner-up Toad Ramsey (499) and 1884 Union Association leader Hugh Daily (483) also do not appear.
In the National League, Charles "Old Hoss" Radbourn struck out 441 batters in 1884 for the Providence Grays; however, the Providence franchise folded after the 1885 season and has no successor. Accordingly, Major League Baseball recognizes the runner-up from 1884, Charlie Buffinton of the Boston Red Sox, as the record-holder with 417 strikeouts. In the American League, Ryan holds the record with 383 strikeouts in 1973.
The largest margin of victory for a champion is 156 strikeouts, achieved in 1883 when Tim Keefe of the American Association's New York Metropolitans 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 largest American League victory. Although ties for the championship are rare, they have occurred; Claude Passeau and Bucky Walters each struck out 137 National League batters in 1939, and Tex Hughson and Bobo Newsom 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 games, 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 Year Links to the corresponding "year in baseball" or "Major League Baseball season" articleLeader Player with the highest number of strikeouts in the leagueK Number of strikeoutsRunner-up Player with the second-best strikeout total in the leagueLeague Denoted only for players outside of the modern major leagues Member of the National Baseball Hall of Fame and Museum
National League
YearLeaderKTeamRunner-upKRef 122 Louisville Grays 103 170 Boston Red Caps 141 182 Boston Red Caps 169 239 Providence Grays 232 268 Chicago White Stockings 260 212 Detroit Wolverines 178 201 Providence Grays 200 345 Boston Beaneaters 315 441 Providence Grays 417 308 Chicago White Stockings 258 323 Detroit Wolverines 313 237 Chicago White Stockings 189 335 New York Giants 223 284 Boston Beaneaters 225 341 New York Giants 289 337 New York Giants 261 314 Chicago White Stockings 304 208 New York Giants 107 195 New York Giants 140 201 New York Giants 148 140 Cleveland Spiders 137 156 Washington SenatorsNew York Giants 149 239 New York Giants 178 145 Cincinnati Reds 142 132 Cincinnati Reds 130 239 Cincinnati Reds 226 225 Boston Beaneaters 185 267 New York Giants 171 212 New York Giants 196 206 New York Giants 198 171 Chicago CubsSt. Louis Cardinals 158 178 New York Giants 147 259 New York Giants 199 205 Chicago Cubs 201 185 Philadelphia Phillies 184 237 New York Giants 227 195 Philadelphia Phillies 176 168 Philadelphia Phillies 167 214 Philadelphia Phillies 189 241 Philadelphia Phillies 176 167 Philadelphia Phillies 166 200 Philadelphia Phillies 195 148 Chicago Cubs 117 141 Chicago Cubs 137 173 Chicago Cubs 131 136 Brooklyn Robins 134 134 Brooklyn Robins 129 197 Brooklyn Robins 151 262 Brooklyn Robins 135 221 Brooklyn Robins 140 140 Brooklyn Robins 127 184 Brooklyn Robins 145 200 Brooklyn Robins 155 166 Chicago Cubs 140 177 St. Louis Cardinals 173 159 St. Louis Cardinals 155 191 St. Louis Cardinals 137 199 St. Louis Cardinals 156 195 St. Louis Cardinals 184 190 St. Louis Cardinals 150 238 Brooklyn Dodgers 195 159 New York Giants 149 135 Chicago Cubs 132 Passeau, Claude; Walters, BuckyClaude PasseauBucky Walters 137 Cincinnati RedsPhiladelphia PhilliesChicago Cubs 130 137 Philadelphia Phillies 124 202 Cincinnati Reds 176 186 Cincinnati Reds 152 174 Cincinnati Reds 141 161 New York Giants 141 148 Pittsburgh Pirates 139 135 Chicago Cubs 134 193 Cincinnati Reds 148 149 St. Louis Cardinals 138 151 Boston Braves 149 191 Boston Braves 188 164 Brooklyn DodgersBoston Braves 146 183 Boston Braves 157 198 Philadelphia Phillies 187 185 Philadelphia Phillies 184 198 Chicago Cubs 160 176 Chicago Cubs 170 188 Philadelphia Phillies 170 225 St. Louis Cardinals 150 242 Los Angeles Dodgers 209 246 Los Angeles Dodgers 197 269 Los Angeles Dodgers 205 232 Los Angeles Dodgers 219 306 Los Angeles Dodgers 265 250 Pittsburgh Pirates 245 382 Los Angeles Dodgers 276 317 Los Angeles Dodgers 252 253 Philadelphia Phillies 236 268 St. Louis Cardinals 260 273 Chicago Cubs 269 283 New York Mets 274 289 New York Mets 263 310 Philadelphia Phillies 249 251 New York Mets 223 240 Philadelphia Phillies 221 243 New York Mets 215 235 New York Mets 214 262 Atlanta Braves 214 303 Houston Astros 248 313 Houston Astros 213 286 Philadelphia Phillies 200 180 Los Angeles Dodgers 179 286 Philadelphia Phillies 274 275 Philadelphia Phillies 242 276 New York Mets 240 268 New York Mets 214 306 Houston Astros 242 270 Houston Astros 233 228 Houston Astros 213 201 St. Louis Cardinals 200 233 New York Mets 223 241 New York Mets † 198 † 215 Atlanta Braves 214 227 Cincinnati Reds † 208 189 San Diego Padres 171 236 Los Angeles Dodgers † 193 † 276 Atlanta Braves 234 319 Philadelphia Phillies † 305 300 Philadelphia Phillies 257 † 364 Arizona Diamondbacks 221 † 347 Arizona Diamondbacks 217 † 372 Arizona Diamondbacks 293 † 334 Arizona Diamondbacks 316 266 Chicago Cubs 245 † 290 Arizona Diamondbacks 264 216 San Diego Padres 213 216 Cincinnati Reds 215 240 San Diego Padres 218 265 San Francisco Giants 206 261 San Francisco Giants 238 231 San Francisco Giants 219 248 Los Angeles Dodgers 238 230 New York Mets 229 232 Los Angeles Dodgers 222 242 Cincinnati RedsWashington Nationals 239 301 Los Angeles Dodgers 276 284 Washington Nationals 253 268 Washington Nationals 239 300 Washington Nationals 269 255 New York Mets 251 104 New York Mets 100 247 Philadelphia Phillies 236 238 Milwaukee Brewers 237 281 Atlanta Braves 234 225 Atlanta Braves 224 224 San Francisco Giants 216 252 Milwaukee Brewers Cristopher Sánchez 221
American League
YearLeaderKTeamRunner-upKRef 158 Boston Americans 127 210 Philadelphia Athletics 160 302 Philadelphia Athletics 187 349 Philadelphia Athletics 239 287 Philadelphia Athletics 210 196 Philadelphia Athletics 178 232 Philadelphia Athletics 206 269 Chicago White Sox 232 177 Chicago White Sox 164 313 Washington Senators 258 255 Chicago White Sox 231 303 Washington Senators 258 243 Washington Senators 166 225 Washington Senators 179 203 Washington Senators 182 228 Washington Senators 182 188 Washington Senators 150 162 Washington Senators 129 147 Washington Senators 128 133 Cleveland Indians 128 143 Washington Senators 132 149 St. Louis Browns 148 130 Washington Senators 125 158 Washington Senators 119 116 Philadelphia Athletics 108 194 Philadelphia Athletics 159 174 Philadelphia Athletics 136 183 Philadelphia Athletics 139 170 Philadelphia Athletics 149 209 Philadelphia Athletics 193 175 Philadelphia Athletics 152 190 New York Yankees 188 163 New York Yankees 149 158 New York Yankees 151 163 Detroit Tigers 140 175 Detroit Tigers 165 194 New York Yankees 166 240 Cleveland Indians 226 246 Cleveland Indians 192 261 Cleveland Indians 164 260 Cleveland Indians 175 113 Boston Red SoxWashington Senators 110 151 Cleveland Indians 144 187 Detroit Tigers 144 212 Detroit Tigers 129 348 Cleveland Indians 275 196 Cleveland Indians 176 164 Cleveland Indians 147 153 Detroit Tigers 144 170 Cleveland Indians 160 164 New York Yankees 133 160 New York Yankees 153 186 Chicago White Sox 149 185 Baltimore Orioles 155 245 Cleveland Indians 210 263 Cleveland Indians 192 184 Cleveland Indians 182 179 Chicago White Sox 177 201 Detroit Tigers 185 201 Detroit Tigers 160 221 Minnesota Twins 209 206 Minnesota Twins 184 202 Minnesota Twins 196 217 New York Yankees 213 325 Cleveland Indians 226 225 Cleveland Indians 205 246 Boston Red Sox 236 283 Cleveland Indians 280 279 Cleveland Indians 271 304 Cleveland Indians 230 308 Detroit Tigers 301 329 California Angels 250 383 California Angels 258 367 California Angels 249 269 California Angels 233 327 California Angels 261 341 California Angels 244 260 California Angels 248 223 California Angels 201 187 Cleveland Indians 180 127 Cleveland Indians 108 209 Seattle Mariners 187 232 Detroit Tigers 193 204 Seattle Mariners 198 206 Cleveland IndiansMinnesota Twins 198 245 Seattle Mariners 238 262 Seattle Mariners 256 291 Boston Red Sox 235 301 Texas Rangers 230 232 Texas Rangers 221 241 Boston Red Sox † 228 † 241 Seattle Mariners 218 † 308 Seattle Mariners 196 † 204 Seattle Mariners 168 † 294 Seattle Mariners 205 257 Boston Red Sox 215 292 Toronto Blue Jays † 291 271 Toronto Blue Jays † 251 † 313 Boston Red Sox 200 † 284 Boston Red Sox 212 220 Boston Red Sox 214 † 239 Boston Red Sox 192 207 Chicago White Sox † 206 265 Minnesota Twins † 227 238 Minnesota Twins † 211 245 Minnesota Twins 202 239 Tampa Bay Devil Rays 235 231 Toronto Blue Jays 214 269 Detroit Tigers 242 233 Los Angeles Angels of Anaheim 232 250 Detroit Tigers † 230 239 Detroit Tigers 231 277 Texas Rangers 240 271 Tampa Bay RaysDetroit Tigers 269 274 Chicago White Sox 252 254 Detroit Tigers 233 308 Boston Red Sox 265 290 Houston Astros 276 326 Houston Astros 300 122 Cleveland Indians 97 248 Toronto Blue Jays 243 257 New York Yankees 227 237 Toronto Blue Jays 234 228 Detroit Tigers 223 255 Boston Red Sox 241 248 Cleveland Guardians 239
Other major leagues