Single-Season ERA
Leaderboard
 
* - Indicates Hall of Fame
Rank    Player ERA IP Year Career Leaderboard
1.    Dennis Baley 1.384 253.7 2022  
2.    J.D. Martin 1.403 231.0 2018  
3.    Mark Prior * 1.482 279.3 2009  
4.    Mark Prior * 1.584 244.3 2011  
5.    Mark Prior * 1.614 206.3 2014  
6.    Mark Prior * 1.641 252.3 2013  
7.    Roger Heitman 1.663 249.0 2013  
8.    Felipe Granados 1.707 263.7 2019  
9.    Korey Mathison 1.734 290.7 2021  
10.    Lewis Washburn 1.816 257.7 2019  
11.    Larry Strope 1.862 261.0 2009  
12.    Augustine Stearn 1.863 236.7 2018  
13.    Mark Prior * 1.886 238.7 2008  
14.    Mark Prior * 1.891 185.7 2015  
15.    Roger Heitman 1.929 224.0 2019  
16.    J.D. Martin 1.966 224.3 2017  
17.    Augustine Stearn 1.971 242.0 2022  
18.    Willie Leon 1.972 237.3 2019  
19.    Lewis Washburn 1.996 239.0 2021  
20.    Roy Halladay 1.997 243.3 2007  
21.    Roger Heitman 2.018 245.3 2016  
22.    Korey Mathison 2.029 261.7 2019  
23.    Augustine Stearn 2.030 248.3 2021  
24.    Mark Prior * 2.056 227.7 2018  
25.    Roger Heitman 2.057 170.7 2017  
26.    Lewis Washburn 2.074 208.3 2020  
27.    Roy Halladay 2.094 240.7 2008  
28.    Mark Prior * 2.114 264.0 2006  
29.    Brian Anderson 2.119 263.3 2014  
30.    Roy Halladay 2.129 266.3 2006  
31.    Zachery Hickman 2.131 245.0 2022  
32.    John Atkins 2.140 164.0 2020  
33.    Roy Halladay 2.144 268.7 2010  
34.    Carlos Silva 2.147 197.0 2014  
35.    Roy Halladay 2.160 275.0 2009  
36.    Joseph Delagarza 2.163 224.7 2021  
37.    Willie Leon 2.177 268.7 2022  
38.    Mark Prior * 2.183 268.0 2007  
39.    Brian Anderson 2.185 263.7 2020  
40.    Henry Mosqueda 2.194 225.7 2021  
41.    Roger Heitman 2.218 235.3 2018  
42.    Freddie Cooley 2.222 263.3 2013  
43.    Korey Mathison 2.224 287.3 2022  
44.    Pedro Martinez 2.239 213.0 2005  
45.    Joe Morgan Jr. 2.253 227.7 2018  
46.    Kevin Rockey 2.260 219.0 2018  
47.    Jeremy Bonderman 2.263 238.7 2012  
48.    Joe Morgan Jr. 2.285 212.7 2012  
49.    Mark Buehrle 2.293 259.0 2005  
50.    Larry Strope 2.313 237.3 2008  
51.    Mark Prior * 2.313 260.7 2005  
52.    J.D. Martin 2.328 212.7 2013  
53.    Larry Strope 2.332 239.3 2015  
54.    J.D. Martin 2.343 226.7 2015  
55.    Lewis Washburn 2.345 238.0 2022  
56.    Dennis Baley 2.356 240.7 2021  
57.    Brian Anderson 2.357 252.0 2021  
58.    J.D. Martin 2.361 209.7 2016  
59.    John Moore 2.362 247.7 2017  
60.    Silvio Santacruz 2.365 255.0 2019  
61.    Felipe Granados 2.372 227.7 2022  
62.    Felipe Granados 2.374 235.0 2021  
63.    Joe Morgan Jr. 2.375 204.7 2020  
64.    Condel Ortiz 2.377 242.3 2015  
65.    Freddie Cooley 2.378 257.3 2016  
66.    J.D. Martin 2.381 234.3 2019  
67.    Condel Ortiz 2.390 252.3 2014  
68.    Bennie Hamblin 2.393 240.7 2020  
69.    Josh Beckett 2.403 221.0 2006  
70.    Mark Prior * 2.407 224.3 2017  
71.    Henry Mosqueda 2.413 257.3 2018  
72.    Adam Muniz 2.417 193.7 2018  
73.    Roger Heitman 2.417 197.3 2014  
74.    Steven Maney 2.420 215.7 2016  
75.    Mark Prior * 2.422 174.7 2004  
76.    Jose Guevara 2.429 226.0 2009  
77.    Willian Larson 2.430 196.3 2021  
78.    Augustine Stearn 2.438 243.7 2020  
79.    Rick Ankiel 2.451 205.7 2013  
80.    Korey Mathison 2.452 286.3 2020  
81.    Richard Menzies 2.455 227.3 2012  
82.    Kevin Rockey 2.455 216.3 2019  
83.    Eric Losey 2.455 245.7 2021  
84.    Silvio Santacruz 2.459 172.0 2022  
85.    Roger Heitman 2.467 266.3 2012  
86.    Brian Anderson 2.470 269.7 2015  
87.    Silvio Santacruz 2.476 232.7 2020  
88.    Dontrelle Willis 2.495 220.0 2006  
89.    Carlos Zambrano 2.497 230.7 2010  
90.    Roy Halladay 2.504 298.3 2005  
91.    Matt Capps 2.505 244.3 2013  
92.    Dennis Baley 2.507 247.7 2020  
93.    Pedro Barranco 2.512 254.3 2011  
94.    Carlos Zambrano 2.516 254.0 2009  
95.    Oliver Perez 2.516 186.0 2008  
96.    Roy Oswalt 2.546 268.7 2004  
97.    Nicholas Lehr 2.549 226.0 2012  
98.    Freddie Cooley 2.555 267.7 2017  
99.    Steven Hildebrant 2.556 225.3 2021  
100.    Rick Hummel 2.557 232.3 2013