Babe Ruth had the best on-base percentage in 1927, with an on-base percentage of .486.

Interpreted as:

best obp with a minimum of 3.1 PA per team game by an MLB player 1927

	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	.486	1927	NYY	151	540	158	192	29	8	60	165	137	0	89	7	6	691	417	97	14	.356	.772	1.258	195	109.9	.545	212	104.8
2	Harry Heilmann H. Heilmann	.475	1927	DET	141	505	106	201	50	9	14	120	72	2	16	11	5	596	311	73	17	.398	.616	1.091	144	70.3	.493	177	62.2
3	Lou Gehrig L. Gehrig	.474	1927	NYY	155	584	149	218	52	18	47	173	109	3	84	10	8	717	447	117	21	.373	.765	1.240	199	110.9	.540	209	105.6
4	Rogers Hornsby R. Hornsby	.448	1927	NYG	155	568	133	205	32	9	26	125	86	4	38	9		684	333	67	26	.361	.586	1.035	151	67.4	.469	176	65.8
5	Max Bishop M. Bishop	.442	1927	PHA	117	372	80	103	15	1	0	22	105	5	28	8	6	489	120	16	7	.277	.323	.764	75	15.2	.384	112	8
6	Ty Cobb T. Cobb	.440	1927	PHA	133	490	104	175	32	7	5	93	67	5	12	22	16	574	236	44	12	.357	.482	.921	109	38.3	.429	138	29.8
7	Paul Waner P. Waner	.437	1927	PIT	155	623	114	237	42	18	9	131	60	3	14	5		709	342	69	23	.380	.549	.986	146	59.3	.450	159	53.3
8	George Harper G. Harper	.435	1927	NYG	145	483	85	160	19	6	16	87	84	5	27	7		593	239	41	21	.331	.495	.930	114	40.8	.432	153	39.4
9	Riggs Stephenson R. Stephenson	.415	1927	CHC	152	579	101	199	46	9	7	82	65	6	28	8		668	284	62	18	.344	.491	.906	121	38.9	.418	145	38.2
10	Earle Combs E. Combs	.414	1927	NYY	152	648	137	231	36	23	6	64	62	2	31	15	6	724	331	65	12	.356	.511	.925	134	45.3	.424	141	40
11	Bob Fothergill B. Fothergill	.413	1927	DET	143	527	93	189	38	9	9	114	47	2	31	9	15	593	272	56	17	.359	.516	.929	111	38.1	.426	138	30.1
12	Mickey Cochrane M. Cochrane	.409	1927	PHA	126	432	80	146	20	6	12	80	50	2	7	9	6	507	214	38	23	.338	.495	.904	91	28.9	.417	131	21.5
13	Ken Williams K. Williams	.403	1927	SLA	131	423	70	136	23	6	17	74	57	1	30	9	7	496	222	46	15	.322	.525	.928	92	31	.424	133	22.4
14	Muddy Ruel M. Ruel	.403	1927	WSH	131	428	61	132	16	5	1	52	63	5	18	9	6	504	161	22	8	.308	.376	.779	74	11.6	.374	110	6.7
15	Joe Harris J. Harris	.402	1927	PIT	129	411	57	134	27	9	5	73	48	4	19	0		486	194	41	23	.326	.472	.874	83	22.9	.404	131	18.8
16	Hack Wilson H. Wilson	.401	1927	CHC	146	551	119	175	30	12	30	129	71	6	70	13		646	319	72	18	.318	.579	.980	129	49.1	.441	159	48.4
17	Alex Metzler A. Metzler	.396	1927	CWS	134	543	87	173	29	11	3	61	61	9	39	15	11	624	233	43	11	.319	.429	.826	97	20.8	.387	119	16.2
18	George Grantham G. Grantham	.396	1927	PIT	151	531	96	162	33	11	8	66	74	6	39	9		634	241	52	23	.305	.454	.850	103	25.4	.395	125	20
19	Lloyd Waner L. Waner	.396	1927	PIT	150	629	133	223	17	6	2	27	37	6	23	14		683	258	25	11	.355	.410	.806	102	18.4	.379	115	12.7
20	Tristram Speaker T. Speaker	.395	1927	WSH	141	523	71	171	43	6	2	73	55	4	8	9	8	597	232	51	15	.327	.444	.839	95	21.8	.391	120	15.9
21	Charlie Jamieson C. Jamieson	.394	1927	CLE	127	489	73	151	23	6	0	36	64	5	14	7	9	572	186	29	14	.309	.380	.775	82	11.2	.370	105	3.5
22	Bob Meusel B. Meusel	.393	1927	NYY	135	516	75	174	47	9	8	103	45	2	58	24	10	584	263	64	21	.337	.510	.902	103	31.1	.412	134	26.8
23	Goose Goslin G. Goslin	.392	1927	WSH	148	581	96	194	37	15	13	120	50	5	28	21	6	659	300	65	23	.334	.516	.908	117	36	.414	133	29.5
24	Bibb Falk B. Falk	.391	1927	CWS	145	535	76	175	35	6	9	83	52	4	19	5	7	613	249	50	22	.327	.465	.856	100	24.9	.396	125	20.4
25	Jim Bottomley J. Bottomley	.387	1927	SLN	152	574	95	174	31	15	19	124	74	5	49	8		679	292	65	26	.303	.509	.896	118	34.4	.409	136	31.2