Jimmie Foxx had the highest on-base percentage in the AL in 1938, with an on-base percentage of .462.

Interpreted as:

best obp with a minimum of 3.1 PA per team game by a player in the al in 1938

	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	Jimmie Foxx J. Foxx	.462	1938	BSA	149	565	139	197	33	9	50	175	119	0	76	5	4	685	398	92	1	.349	.704	1.166	178	91.7	.508	173	74.2
2	Buddy Myer B. Myer	.454	1938	WSH	127	437	79	147	22	8	6	71	93	1	32	9	5	534	203	36	3	.336	.465	.918	104	37.1	.429	137	28.8
3	Hank Greenberg H. Greenberg	.438	1938	DET	155	556	143	175	23	4	58	147	119	3	92	7	5	681	380	85	3	.315	.683	1.122	166	80.3	.489	162	62
4	Earl Averill E. Averill	.429	1938	CLE	134	482	101	159	27	15	14	93	81	3	48	5	2	567	258	56	1	.330	.535	.965	114	43.2	.437	138	31.5
5	Joe Cronin J. Cronin	.428	1938	BSA	143	530	98	172	51	5	17	94	91	5	60	7	5	637	284	73	11	.325	.536	.964	129	48.6	.437	134	32.3
6	Charlie Gehringer C. Gehringer	.425	1938	DET	152	568	133	174	32	5	20	107	113	4	21	14	1	688	276	57	3	.306	.486	.911	129	42.7	.420	124	24.3
7	Harlond Clift H. Clift	.423	1938	SLA	149	534	119	155	25	7	34	118	118	5	67	10	5	658	296	66	1	.290	.554	.977	134	51.6	.440	134	33.1
8	Ben Chapman B. Chapman	.418	1938	BSA	127	480	92	163	40	8	6	80	65	0	33	13	6	553	237	54	8	.340	.494	.912	103	33.5	.418	124	19.3
9	Rudy York R. York	.417	1938	DET	135	463	86	138	27	2	33	126	92	2	74	1	2	557	268	62	0	.298	.579	.995	116	45.8	.445	138	30.8
10	Bill Dickey B. Dickey	.412	1938	NYY	132	454	84	142	27	4	27	115	75	2	22	3	0	532	258	58	1	.313	.568	.981	108	41.5	.440	142	32.5
11	Lou Gehrig L. Gehrig	.410	1938	NYY	157	576	115	170	32	6	29	114	107	5	75	6	1	689	301	67	1	.295	.523	.932	131	44.6	.423	133	33
12	Hal Trosky Sr. H. Trosky Sr.	.407	1938	CLE	150	554	106	185	40	9	19	110	67	1	40	5	1	626	300	68	4	.334	.542	.948	121	42.9	.428	133	30
13	Bob Johnson B. Johnson	.406	1938	PHA	152	563	114	176	27	9	30	113	87	2	73	9	8	652	311	66	0	.313	.552	.959	128	46.3	.431	133	31.3
14	Rick Ferrell R. Ferrell	.401	1938	WSH	135	411	55	120	24	5	1	58	75	0	17	1	0	495	157	30	9	.292	.382	.783	74	12	.373	106	4.3
15	Cecil Travis C. Travis	.401	1938	WSH	146	567	96	190	30	5	5	67	58	4	22	6	5	642	245	40	13	.335	.432	.833	104	23.2	.388	114	13.2
16	Dixie Walker D. Walker	.396	1938	DET	127	454	84	140	27	6	6	43	65	1	32	5	4	526	197	39	6	.308	.434	.830	84	18.3	.386	105	4.2
17	Tommy Henrich T. Henrich	.391	1938	NYY	131	471	109	127	24	7	22	91	92	2	32	6	2	575	231	53	10	.270	.490	.882	100	27.5	.402	121	17.8
18	Pinky Higgins P. Higgins	.388	1938	BSA	139	524	77	159	29	5	5	106	71	1	55	10	9	603	213	39	7	.303	.406	.794	90	14.2	.372	99	-1.2
19	Joe DiMaggio J. DiMaggio	.386	1938	NYY	145	599	129	194	32	13	32	140	59	2	21	6	1	660	348	77	0	.324	.581	.967	129	46.5	.430	136	35.4
20	Red Rolfe R. Rolfe	.386	1938	NYY	151	631	132	196	36	8	10	80	74	3	44	13	1	714	278	54	6	.311	.441	.826	112	22.6	.382	110	10.6
21	George McQuinn G. McQuinn	.384	1938	SLA	148	602	100	195	42	7	12	82	58	1	49	4	5	674	287	61	13	.324	.477	.861	112	27.4	.394	109	8.5
22	Joe Vosmik J. Vosmik	.384	1938	BSA	146	621	121	201	37	6	9	86	59	2	26	0	3	689	277	52	7	.324	.446	.830	109	22.2	.383	105	4.6
23	Jeff Heath J. Heath	.383	1938	CLE	126	502	104	172	31	18	21	112	33	0	55	3	1	538	302	70	3	.343	.602	.985	108	40.3	.436	137	29.3
24	Frankie Crosetti F. Crosetti	.382	1938	NYY	157	631	113	166	35	3	9	55	106	15	97	27	12	757	234	47	5	.263	.371	.752	105	10.2	.360	98	-2.5
25	Red Kress R. Kress	.378	1938	SLA	150	566	74	171	33	3	7	79	69	0	47	5	4	644	231	43	9	.302	.408	.786	93	12.5	.367	94	-5.6