who has the lowest era of all-time minimum 300 ip

Al Spalding has the lowest career ERA when pitching at least 300 innings, with an ERA of 1.78.

	NAME	ERA	IP	G	W	L	W%	GS	SO	CG	SHO	SV	H	ER	R	HR	BB	HBP	GF	IBB	TBF	WP	K/9	BB/9	K/BB	HR/9	K%	BB%	WHIP	BABIP	RA	ERA-	FIP	FIP-	H/9	PRAA
1	Al Spalding A. Spalding	1.78	539.2	65	48	12	.800	61	41	53	8	1	559	107	238	6	26		4		2,272	1	0.68	0.43	1.58	0.10	1.8	1.1	1.08		3.97	74	2.38	99	9.32	9.6
2	Ed Walsh E. Walsh	1.82	2964.1	430	195	126	.607	315	1,736	250	57	35	2,346	598	873	23	617	52	105		11,413	76	5.27	1.87	2.81	0.07	15.2	5.4	1.00	.259	2.65	69	2.02	79	7.12	164.3
3	Emmanuel Clase E. Clase	1.88	360.0	366	21	25	.457	1	349	0	0	182	267	75	111	15	70	9	297	10	1,417	19	8.73	1.75	4.99	0.38	24.6	4.9	0.94	.259	2.78	45	2.43	58	6.68	68.8
4	Addie Joss A. Joss	1.89	2327.0	286	160	97	.623	260	920	234	45	5	1,888	488	730	19	364	58	22		8,891	28	3.56	1.41	2.53	0.07	10.3	4.1	0.97	.248	2.82	70	2.25	86	7.30	88.8
5	Jim Devlin J. Devlin	1.89	1181.0	129	65	60	.520	129	263	127	9	0	1,183	248	597	7	78		0		4,896	34	2.00	0.59	3.37	0.05	5.4	1.6	1.07		4.55	67	2.35	84	9.02	88.9
6	Paul Skenes P. Skenes	1.96	320.2	55	21	13	.618	55	386	1	0	0	230	70	76	21	74	12	0	0	1,247	4	10.83	2.08	5.22	0.59	31.0	5.9	0.95	.277	2.13	46	2.39	58	6.46	61
7	Jack Pfiester J. Pfiester	2.02	1067.1	149	71	44	.617	128	503	75	17	0	869	240	365	6	293	39	12		4,236	16	4.24	2.47	1.72	0.05	11.9	6.9	1.09	.254	3.08	77	2.32	86	7.33	44.3
8	Joe Wood J. Wood	2.03	1434.1	225	117	57	.672	158	989	121	28	10	1,138	324	497	10	421	49	56		5,640	43	6.21	2.64	2.35	0.06	17.5	7.5	1.09	.270	3.12	70	2.26	78	7.14	105.8
9	Mordecai Brown M. Brown	2.06	3172.1	481	239	130	.648	332	1,375	271	55	49	2,708	725	1,044	43	673	61	138		12,422	61	3.90	1.91	2.04	0.12	11.1	5.4	1.07	.259	2.96	71	2.42	83	7.68	161.9
10	John Ward J. Ward	2.10	2469.2	293	164	103	.614	262	920	245	24	3	2,324	576	1,185	26	253		32		10,164	144	3.35	0.92	3.64	0.09	9.1	2.5	1.04		4.32	82	2.43	96	8.47	9.1
11	Christy Mathewson C. Mathewson	2.13	4788.2	636	373	188	.665	552	2,507	435	79	30	4,219	1,135	1,620	89	848	59	73		18,913	115	4.71	1.59	2.96	0.17	13.3	4.5	1.06	.268	3.04	75	2.26	76	7.93	363
12	Rube Waddell R. Waddell	2.16	2961.1	407	193	143	.574	340	2,316	261	50	5	2,460	711	1,063	37	803	115	54		11,717	74	7.04	2.44	2.88	0.11	19.8	6.9	1.10	.287	3.23	75	2.03	71	7.48	262
13	Walter Johnson W. Johnson	2.17	5914.1	802	417	279	.599	666	3,509	531	110	34	4,913	1,424	1,902	97	1,363	205	127		23,405	154	5.34	2.07	2.57	0.15	15.0	5.8	1.06	.264	2.89	68	2.42	76	7.48	472.8
14	Glenn Liebhardt G. Liebhardt	2.17	612.2	90	36	35	.507	66	280	49	7	2	543	148	225	3	183	14	23		2,419	21	4.11	2.69	1.53	0.04	11.6	7.6	1.18	.278	3.31	89	2.27	98	7.98	1.6
15	Mellie Wolfgang M. Wolfgang	2.18	326.0	77	15	14	.517	27	111	15	3	0	268	79	115	3	95	4	37		1,269	3	3.06	2.62	1.17	0.08	8.7	7.5	1.11	.251	3.17	79	2.72	97	7.40	3
16	Mariano Rivera M. Rivera	2.21	1283.2	1,115	82	60	.577	10	1,173	0	0	652	998	315	340	71	286	46	952	41	5,103	13	8.22	2.01	4.10	0.50	23.0	5.6	1.00	.263	2.38	49	2.76	61	7.00	246.7
17	Jake Weimer J. Weimer	2.23	1472.2	191	97	69	.584	180	657	143	21	2	1,227	365	511	14	493	73	9		5,971	26	4.02	3.01	1.33	0.09	11.0	8.3	1.17	.256	3.12	81	2.81	98	7.50	8.7
18	Tommy Bond T. Bond	2.25	2779.2	322	193	115	.627	314	860	294	35	0	2,857	695	1,339	32	178		11		11,386	120	2.78	0.58	4.83	0.10	7.6	1.6	1.09	.274	4.34	89	2.38	95	9.25	32.3
19	Orval Overall O. Overall	2.26	1535.1	218	108	71	.603	182	935	133	30	12	1,232	385	520	16	551	45	30		6,145	57	5.48	3.23	1.70	0.09	15.2	9.0	1.16	.264	3.05	81	2.39	85	7.22	72.4
20	Will White W. White	2.28	3542.2	403	229	166	.580	402	1,041	394	36	0	3,440	896	1,844	65	496		1		14,951	221	2.64	1.26	2.10	0.17	7.0	3.3	1.11	.254	4.68	83	2.98	108	8.74	-109.3
21	Bill James B. James	2.28	541.2	84	37	21	.638	60	253	44	5	3	469	137	196	14	199	22	20		2,217	17	4.20	3.31	1.27	0.23	11.4	9.0	1.23	.263	3.26	75	3.09	99	7.79	4.8
22	Babe Ruth B. Ruth	2.28	1221.1	163	94	46	.671	147	488	107	17	4	974	309	400	10	441	29	12		4,896	25	3.60	3.25	1.11	0.07	10.0	9.0	1.16	.245	2.95	82	2.81	100	7.18	-6.6
23	Ed Reulbach E. Reulbach	2.28	2632.1	399	182	106	.632	300	1,137	200	40	13	2,117	668	887	33	892	107	80		10,521	49	3.89	3.05	1.27	0.11	10.8	8.5	1.14	.250	3.03	80	2.84	99	7.24	9
24	Frank Arellanes F. Arellanes	2.28	409.2	74	24	22	.522	49	148	25	2	8	358	104	147	5	85	11	23		1,602	8	3.25	1.87	1.74	0.11	9.2	5.3	1.08	.261	3.23	91	2.36	96	7.86	4.4
25	Nick Maddox N. Maddox	2.29	605.1	93	43	20	.683	72	193	47	9	1	487	154	209	7	170	35	18		2,368	8	2.87	2.53	1.14	0.10	8.2	7.2	1.09	.245	3.11	90	2.71	104	7.24	-6.7