highest win percentage by a starting pitcher since 1940 with at least 20 starts

Since 1940, Freddie Fitzsimmons has the best win percentage by a starting pitcher when starting 20+ games, at .793.

	NAME	W%	GS	W	L	G	ERA	SO	CG	SHO	SV	IP	H	ER	R	HR	BB	HBP	GF	IBB	TBF	WP	K/9	BB/9	K/BB	HR/9	K%	BB%	WHIP	BABIP	RA	H/9
1	Freddie Fitzsimmons F. Fitzsimmons	.793	38	23	6	38	3.16	60	15	5	0	247.2	243	87	104	14	70	4	0		1,047	2	2.18	2.54	0.86	0.51	5.7	6.7	1.26	.255	3.78	8.83
2	Shota Imanaga S. Imanaga	.783	37	18	5	37	2.89	208	0	0	0	218.0	184	70	81	34	42	3	0	0	875	3	8.59	1.73	4.95	1.40	23.8	4.8	1.04	.255	3.34	7.60
3	Howie Krist H. Krist	.783	33	18	5	33	3.70	79	14	2	0	231.0	234	95	101	7	78	6	0		984	4	3.08	3.04	1.01	0.27	8.0	7.9	1.35	.279	3.94	9.12
4	Parker Bridwell P. Bridwell	.769	21	10	3	21	4.16	72	0	0	0	119.0	115	55	57	22	30	4	0	0	489	4	5.45	2.27	2.40	1.66	14.7	6.1	1.22	.258	4.31	8.70
5	Terry Leach T. Leach	.750	21	12	4	21	3.39	57	3	3	0	130.0	122	49	56	11	36	0	0	3	540	0	3.95	2.49	1.58	0.76	10.6	6.7	1.22	.255	3.88	8.45
6	Johnny Beazley J. Beazley	.735	46	25	9	46	3.01	114	21	3	0	317.0	307	106	126	12	134	5	0		1,359	13	3.24	3.80	0.85	0.34	8.4	9.9	1.39	.270	3.58	8.72
7	Tony Gonsolin T. Gonsolin	.733	78	33	12	78	3.28	365	0	0	0	389.1	280	142	151	50	138	15	0	2	1,574	14	8.44	3.19	2.64	1.16	23.2	8.8	1.07	.229	3.49	6.47
8	Erik Hiljus E. Hiljus	.727	20	8	3	20	5.08	84	0	0	0	102.2	113	58	62	18	38	0	0	2	455	3	7.36	3.33	2.21	1.58	18.5	8.4	1.47	.302	5.44	9.91
9	Curt Raydon C. Raydon	.727	20	8	3	20	3.72	70	2	1	0	113.2	104	47	54	14	52	4	0	4	491	2	5.54	4.12	1.35	1.11	14.3	10.6	1.37	.256	4.28	8.23
10	Grayson Rodriguez G. Rodriguez	.714	43	20	8	43	4.11	259	0	0	0	238.2	230	109	114	31	78	7	0	0	1,006	10	9.77	2.94	3.32	1.17	25.7	7.8	1.29	.315	4.30	8.67
11	Tom Acker T. Acker	.714	23	10	4	23	5.17	80	5	1	0	127.0	142	73	73	17	40	4	0	2	553	3	5.67	2.83	2.00	1.20	14.5	7.2	1.43	.303	5.17	10.06
12	Spud Chandler S. Chandler	.714	151	85	34	151	2.61	536	89	22	0	1188.2	1,020	345	411	48	379	16	0		4,845	17	4.06	2.87	1.41	0.36	11.1	7.8	1.18	.251	3.11	7.72
13	Julio Urías J. Urías	.709	122	56	23	122	3.21	643	0	0	0	650.0	551	232	254	79	168	25	0	4	2,644	10	8.90	2.33	3.83	1.09	24.3	6.4	1.11	.273	3.52	7.63
14	Dick Hughes D. Hughes	.708	34	17	7	34	2.90	170	13	4	0	242.1	182	78	84	23	55	5	0	6	956	6	6.31	2.04	3.09	0.85	17.8	5.8	0.98	.226	3.12	6.76
15	Joe Nathan J. Nathan	.706	29	12	5	29	4.60	95	0	0	0	162.1	150	83	95	24	96	5	0	4	723	6	5.27	5.32	0.99	1.33	13.1	13.3	1.52	.250	5.27	8.32
16	Bob Wickman B. Wickman	.700	28	14	6	28	4.66	72	1	1	0	164.0	187	85	98	16	77	6	0	5	734	4	3.95	4.23	0.94	0.88	9.8	10.5	1.61	.304	5.38	10.26
17	Max Fried M. Fried	.697	168	83	36	168	2.94	939	6	4	0	967.1	845	316	352	79	252	40	0	5	3,932	43	8.74	2.34	3.73	0.74	23.9	6.4	1.13	.292	3.27	7.86
18	Whitey Ford W. Ford	.696	438	227	99	438	2.71	1,857	156	45	0	3038.0	2,647	916	1,050	220	1,014	27	0	39	12,468	72	5.50	3.00	1.83	0.65	14.9	8.1	1.21	.260	3.11	7.84
19	Clayton Kershaw C. Kershaw	.696	436	215	94	436	2.51	2,987	25	15	0	2771.1	2,120	774	849	231	688	44	0	27	10,937	105	9.70	2.23	4.34	0.75	27.3	6.3	1.01	.270	2.76	6.88
20	Spencer Strider S. Strider	.696	62	32	14	62	3.63	511	0	0	0	345.0	259	139	148	36	114	16	0	2	1,412	12	13.33	2.97	4.48	0.94	36.2	8.1	1.08	.303	3.86	6.76
21	Al Corwin A. Corwin	.692	22	9	4	22	3.84	53	6	2	0	122.0	120	52	56	14	47	1	0		519	0	3.91	3.47	1.13	1.03	10.2	9.1	1.37	.262	4.13	8.85
22	Jose Fernandez J. Fernandez	.691	76	38	17	76	2.58	589	0	0	0	471.1	357	135	150	31	140	13	0	12	1,888	16	11.25	2.67	4.21	0.59	31.2	7.4	1.05	.292	2.86	6.82
23	Gavin Stone G. Stone	.688	29	11	5	29	4.51	123	1	1	0	155.2	165	78	79	21	45	2	0	0	664	9	7.11	2.60	2.73	1.21	18.5	6.8	1.35	.304	4.57	9.54
24	Don Gullett D. Gullett	.686	186	96	44	186	3.17	796	44	14	0	1243.2	1,088	438	482	108	435	11	0	29	5,155	31	5.76	3.15	1.83	0.78	15.4	8.4	1.22	.258	3.49	7.87
25	Pedro Martinez P. Martinez	.682	409	208	97	409	2.95	3,032	46	17	0	2720.0	2,151	893	979	233	705	136	0	26	10,955	60	10.03	2.33	4.30	0.77	27.7	6.4	1.05	.280	3.24	7.12