Babe Ruth had the highest on-base percentage in 1920, with an on-base percentage of .532.

Interpreted as:

best obp with a minimum of 3.1 PA per team game by an MLB player 1920

	NAME	OBP	SEASON	TM	G	AB	R	H	2B	3B	HR	RBI	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	AVG	SLG	OPS	WRC	WRAA	WOBA	WRC+	BRAA
1	Babe Ruth B. Ruth	.532	1920	NYY	142	458	158	172	36	9	54	135	150	3	80	14	14	616	388	99	5	.376	.847	1.379	191	120.9	.597	237	110.5
2	Tristram Speaker T. Speaker	.483	1920	CLE	150	552	137	214	50	11	8	107	97	5	13	10	13	674	310	69	20	.388	.562	1.045	152	74.9	.483	170	62
3	George Sisler G. Sisler	.449	1920	SLA	154	631	137	257	49	18	19	122	46	2	19	42	17	692	399	86	13	.407	.632	1.082	161	82.5	.494	176	68.6
4	Joe Jackson J. Jackson	.444	1920	CWS	146	570	105	218	42	20	12	121	56	7	14	9	12	649	336	74	16	.382	.589	1.033	141	67.4	.474	167	56.5
5	Eddie Collins E. Collins	.438	1920	CWS	153	602	117	224	38	13	3	76	69	2	19	20	8	706	297	54	33	.372	.493	.932	133	53.1	.435	145	41.2
6	Rogers Hornsby R. Hornsby	.431	1920	SLN	149	589	96	218	44	20	9	94	60	3	50	12	15	660	329	73	8	.370	.559	.990	135	59.4	.455	187	63.2
7	Ross Youngs R. Youngs	.427	1920	NYG	153	581	92	204	27	14	6	78	75	2	55	18	18	671	277	47	13	.351	.477	.904	121	44.5	.423	165	48.3
8	Ty Cobb T. Cobb	.416	1920	DET	112	428	87	143	28	8	2	63	58	2	28	15	10	495	193	38	7	.334	.451	.867	84	27.2	.408	130	19.5
9	Joe Judge J. Judge	.416	1920	WSH	126	493	103	164	19	15	5	51	65	5	34	12	12	576	228	39	13	.333	.462	.878	99	33.3	.412	134	25.7
10	Harry Hooper H. Hooper	.411	1920	BSA	139	536	91	167	30	17	7	53	88	2	27	16	18	631	252	54	5	.312	.470	.881	108	36.5	.412	136	29.5
11	Steve O'Neill S. O'Neill	.408	1920	CLE	149	489	63	157	39	5	3	55	69	3	39	3	5	576	215	47	15	.321	.440	.848	94	28.4	.401	123	17.4
12	Baby Doll Jacobson B. Doll Jacobson	.402	1920	SLA	154	609	97	216	34	14	9	122	46	2	37	11	7	673	305	57	16	.355	.501	.903	119	42.3	.419	133	28.7
13	Braggo Roth B. Roth	.395	1920	WSH	138	468	80	136	23	8	9	92	75	6	57	24	12	561	202	40	12	.291	.432	.827	88	23.9	.392	122	16.4
14	Elmer Smith E. Smith	.391	1920	CLE	129	456	82	144	37	10	12	103	53	3	35	5	4	525	237	59	13	.316	.520	.910	93	33.4	.420	134	23.4
15	Edd Roush E. Roush	.386	1920	CIN	149	579	81	196	22	16	4	90	42	3	22	36	24	650	262	42	26	.339	.453	.839	102	27.7	.392	146	32.9
16	Zack Wheat Z. Wheat	.385	1920	BKN	148	583	89	191	26	13	9	73	48	6	21	8	10	643	270	48	6	.328	.463	.848	103	29.3	.396	143	30.9
17	Happy Felsch H. Felsch	.384	1920	CWS	142	556	88	188	40	15	14	115	37	4	25	8	13	613	300	69	16	.338	.540	.923	111	40.9	.424	138	30.6
18	Jack Tobin J. Tobin	.383	1920	SLA	147	593	94	202	34	10	4	62	39	2	23	21	13	652	268	48	18	.341	.452	.835	101	27	.390	116	13.9
19	Mike Menosky M. Menosky	.383	1920	BSA	141	532	80	158	24	9	3	64	65	9	52	23	19	627	209	36	21	.297	.393	.776	88	16.6	.370	112	9.7
20	Ralph Young R. Young	.382	1920	DET	150	594	84	173	21	6	0	33	85	2	30	8	13	703	206	27	22	.291	.347	.729	90	9.8	.353	99	-1.2
21	Sam Rice S. Rice	.381	1920	WSH	153	624	83	211	29	9	3	80	39	4	23	63	30	686	267	41	19	.338	.428	.809	101	23.2	.380	116	14
22	Ray Chapman R. Chapman	.380	1920	CLE	111	435	97	132	27	8	3	49	52	2	38	13	9	530	184	38	41	.303	.423	.803	78	17.5	.379	111	7.4
23	Bucky Harris B. Harris	.377	1920	WSH	136	506	76	152	26	6	1	68	41	21	36	16	17	592	193	33	24	.300	.381	.758	80	12.6	.363	106	4.6
24	Heinie Groh H. Groh	.375	1920	CIN	145	550	86	164	28	12	0	49	60	8	29	16	19	632	216	40	14	.298	.393	.768	86	14.4	.365	128	19.5
25	Max Flack M. Flack	.373	1920	CHC	135	520	85	157	30	6	4	49	52	7	15	13	19	592	211	40	13	.302	.406	.779	83	15.2	.369	126	17.2