Most Strikeouts by a Pitcher in a Season: Leaders & Records

Single Season

Includes the 2026 season through August 26, 2026

This board follows the record MLB adopted in 2024, when the statistics of the seven recognised Negro Leagues (1920–1948) became part of the official record. Because a Negro Leagues season ran roughly 69 games to the American and National Leagues’ 149, the career qualification is prorated from 3,000 at-bats to 1,389 for careers played mainly in those leagues, and from 400 plate appearances to 185 for a single Negro Leagues season. The all-time AL & NL board uses the traditional 3,000-at-bat rule and excludes Negro Leagues records.

Matt Kilroy holds the MLB single-season strikeout record with 513 strikeouts in 1886, ahead of Toad Ramsey (499 in 1886) and Hugh Daily (469 in 1884).

Rankings cover the top 100 seasons in MLB history.

Top 10 SO

Single Season. Click a bar to view the player.

Rank Player Year Team SO
1 Matt Kilroy 1886 BL2 513
2 Toad Ramsey 1886 LS2 499
3 Hugh Daily 1884 CHU 469
4 Old Hoss Radbourn 1884 PRO 441
5 Charlie Buffinton 1884 BSN 417
6 Guy Hecker 1884 LS2 385
7 Nolan Ryan 1973 CAL 383
8 Sandy Koufax 1965 LAN 382
9 Bill Sweeney 1884 BLU 374
10 Randy Johnson 2001 ARI 372
11 Pud Galvin 1884 BFN 369
12 Mark Baldwin 1889 CL6 368
13 Nolan Ryan 1974 CAL 367
14 Randy Johnson 1999 ARI 364
15 Tim Keefe 1883 NY4 359
16 Toad Ramsey 1887 LS2 355
17 Rube Waddell 1904 PHA 349
18 Bob Feller 1946 CLE 348
19 Randy Johnson 2000 ARI 347
20 Hardie Henderson 1884 BL2 346
T-21 Mickey Welch 1884 NY1 345
T-21 Jim Whitney 1883 BSN 345
T-23 Amos Rusie 1890 NY1 341
T-23 Nolan Ryan 1977 CAL 341
25 Amos Rusie 1891 NY1 337
26 Tim Keefe 1888 NY1 335
T-27 Randy Johnson 2002 ARI 334
T-27 Tim Keefe 1884 NY4 334
29 Nolan Ryan 1972 CAL 329
30 Nolan Ryan 1976 CAL 327
T-31 Gerrit Cole 2019 HOU 326
T-31 Ed Morris 1886 PT1 326
T-33 Sam McDowell 1965 CLE 325
T-33 Tony Mullane 1884 TL1 325
35 Lady Baldwin 1886 DTN 323
36 Curt Schilling 1997 PHI 319
37 Sandy Koufax 1966 LAN 317
38 Curt Schilling 2002 ARI 316
39 Old Hoss Radbourn 1883 PRO 315
40 Bill Hutchison 1892 CHN 314
T-41 John Clarkson 1886 CHN 313
T-41 Walter Johnson 1910 WS1 313
T-41 Pedro Martinez 1999 BOS 313
T-41 J. R. Richard 1979 HOU 313
45 Steve Carlton 1972 PHI 310
46 Dupee Shaw 1884 BSU 309
T-47 John Clarkson 1885 CHN 308
T-47 Randy Johnson 1993 SEA 308
T-47 Mickey Lolich 1971 DET 308
T-47 Larry McKeon 1884 IN2 308
T-47 Chris Sale 2017 BOS 308
T-52 Sandy Koufax 1963 LAN 306
T-52 Mike Scott 1986 HOU 306
54 Pedro Martinez 1997 MON 305
T-55 Sam McDowell 1970 CLE 304
T-55 Amos Rusie 1892 NY1 304
T-57 Walter Johnson 1912 WS1 303
T-57 J. R. Richard 1978 HOU 303
T-59 Ed Morris 1884 CL5 302
T-59 Rube Waddell 1903 PHA 302
T-61 Vida Blue 1971 OAK 301
T-61 Clayton Kershaw 2015 LAN 301
T-61 Nolan Ryan 1989 TEX 301
T-64 Max Scherzer 2018 WAS 300
T-64 Curt Schilling 1998 PHI 300
T-64 Justin Verlander 2019 HOU 300
67 Ed Morris 1885 PT1 298
68 Tim Keefe 1886 NY1 297
69 Randy Johnson 1995 SEA 294
70 Curt Schilling 2001 ARI 293
T-71 Roger Clemens 1997 TOR 292
T-71 Jack Lynch 1884 NY4 292
T-73 Roger Clemens 1988 BOS 291
T-73 Randy Johnson 1997 SEA 291
T-75 Randy Johnson 2004 ARI 290
T-75 Justin Verlander 2018 HOU 290
T-77 Bill Hutchison 1890 CHN 289
T-77 Tom Seaver 1971 NYN 289
T-77 Jack Stivetts 1890 SL4 289
80 Rube Waddell 1905 PHA 287
T-81 Steve Carlton 1980 PHI 286
T-81 Steve Carlton 1982 PHI 286
T-81 Bobby Mathews 1884 PH4 286
T-81 Bobby Mathews 1885 PH4 286
T-85 John Clarkson 1889 BSN 284
T-85 Pedro Martinez 2000 BOS 284
T-85 Max Scherzer 2016 WAS 284
T-88 Dave Foutz 1886 SL4 283
T-88 Sam McDowell 1968 CLE 283
T-88 Tom Seaver 1970 NYN 283
91 Spencer Strider 2023 ATL 281
92 Denny McLain 1968 DET 280
T-93 Pud Galvin 1883 BFN 279
T-93 Sam McDowell 1969 CLE 279
95 Yu Darvish 2013 TEX 277
T-96 Gerrit Cole 2018 HOU 276
T-96 Dwight Gooden 1984 NYN 276
T-96 Max Scherzer 2015 WAS 276
T-96 John Smoltz 1996 ATL 276
T-96 Bob Veale 1965 PIT 276

Frequently Asked Questions

Who has the most strikeouts in a season?
Matt Kilroy — 513 strikeouts in 1886. Next are Toad Ramsey (499 in 1886) and Hugh Daily (469 in 1884).
How many strikeouts did Matt Kilroy record in 1886?
Matt Kilroy recorded 513 strikeouts for BL2 in 1886 — the highest mark on this leaderboard.
Who else ranks in the top 5 for strikeouts in a season?
1. Matt Kilroy (513 in 1886); 2. Toad Ramsey (499 in 1886); 3. Hugh Daily (469 in 1884); 4. Old Hoss Radbourn (441 in 1884); 5. Charlie Buffinton (417 in 1884).
How many seasons are ranked on this leaderboard?
This page lists the top 100 seasons by strikeouts in a season, from Matt Kilroy at 513 down to Bob Veale at 276.