Ted Williams had the highest on-base percentage by a player in his first 7 seasons, with an on-base percentage of .488.

Interpreted as:

highest obp with a minimum of 1.55 PA per team game by a player first 7 seasons

	NAME	OBP	G	AB	R	H	2B	3B	HR	RBI	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	SF	IBB	GIDP	AVG	SLG	OPS	WRC	WRAA	WOBA	WRC+	BRAA
1	Ted Williams T. Williams	.488	1,029	3,655	932	1,294	275	53	222	879	939	19	328	15		4,618	2,341	550	5			77	.354	.640	1.129	1135	605.6	.507	193	532.2
2	Frank Thomas F. Thomas	.452	930	3,291	675	1,077	211	8	222	729	770	23	513	17	14	4,140	1,970	441	0	56	109	108	.327	.599	1.050	897	403.8	.447	177	396
3	Babe Ruth B. Ruth	.451	533	1,568	360	514	118	39	103	359	340	11	264	27		1,943	1,019	260	24				.328	.650	1.101	453	250	.505	200	231.9
4	Billy Hamilton B. Hamilton	.449	781	3,153	879	1,078	125	61	19	384	548	64	83	543		3,772	1,382	205	7				.342	.438	.887	877	296.7	.432	144	267.5
5	Wade Boggs W. Boggs	.445	1,027	3,913	710	1,392	263	29	61	469	647	10	288	12	16	4,629	1,896	353	23	36	68	104	.356	.485	.929	864	336.6	.411	153	293.2
6	Joe Jackson J. Jackson	.444	601	2,239	435	844	152	80	21	314	240	30	136	128		2,556	1,219	253	47				.377	.544	.988	539	250.5	.465	177	232.9
7	Bill Joyce B. Joyce	.443	761	2,802	731	840	133	97	60	518	633	90	243	232		3,544	1,347	290	19				.300	.481	.924	829	278.8	.439	142	246.5
8	Joe Kelley J. Kelley	.441	725	2,834	730	980	171	91	38	574	445	39	182	274		3,363	1,447	300	45				.346	.511	.952	810	270.8	.445	142	244.1
9	John McGraw J. McGraw	.440	588	2,249	557	731	73	42	9	306	406	55	89	253		2,738	915	124	28				.325	.407	.847	588	149.1	.417	127	123.9
10	Lou Gehrig L. Gehrig	.436	767	2,746	631	919	206	72	146	635	480	15	351	30		3,321	1,707	424	80				.335	.622	1.058	743	327.2	.470	170	313.1
11	Roy Thomas R. Thomas	.435	973	3,592	758	1,115	53	30	5	219	739	55	365	191		4,498	1,243	88	112				.310	.346	.781	772	225.9	.391	135	202.1
12	Cupid Childs C. Childs	.434	776	3,036	749	963	123	63	16	432	587	37	99	181		3,672	1,260	202	12				.317	.415	.849	790	217.6	.416	133	187.7
13	Lefty O'Doul L. O'Doul	.431	484	1,592	347	583	93	17	62	275	173	9	56	15		1,805	896	172	31				.366	.563	.994	383	144	.444	138	104
14	Willie Keeler W. Keeler	.431	685	2,981	777	1,147	113	73	16	394	192	51	44	248		3,295	1,454	202	71				.385	.488	.919	736	219.8	.432	137	196
15	Mickey Mantle M. Mantle	.427	952	3,418	763	1,080	164	49	207	669	670	5	653	59	19	4,116	1,963	420	9	14	35	26	.316	.574	1.002	836	364.3	.441	172	361
16	Jesse Burkett J. Burkett	.426	801	3,351	811	1,166	146	89	35	470	428	27	179	193		3,828	1,595	270	22				.348	.476	.902	865	262.6	.427	135	223.3
17	Stan Musial S. Musial	.426	915	3,521	687	1,225	261	95	110	583	458	19	161	41		4,026	2,006	466	28			70	.348	.570	.995	815	376.2	.457	173	340.4
18	Todd Helton T. Helton	.425	981	3,504	717	1,182	279	20	219	740	540	28	470	27	23	4,115	2,158	518	2	41	90	85	.337	.616	1.041	875	359	.435	143	233.2
19	Arky Vaughan A. Vaughan	.425	997	3,705	660	1,231	201	83	65	569	570	29	169	54		4,362	1,793	349	58				.332	.484	.909	817	272.5	.418	150	273.3
20	Ferris Fain F. Fain	.423	972	3,437	533	1,001	192	29	41	488	770	16	222	36	10	4,264	1,374	262	41			105	.291	.400	.823	679	178.7	.392	127	139.9
21	Paul Waner P. Waner	.422	1,051	4,135	800	1,452	299	112	60	625	478	25	136	74		4,735	2,155	471	97				.351	.521	.943	917	317	.427	143	270.8
22	Jake Stenzel J. Stenzel	.421	581	2,332	541	831	160	58	30	456	227	35	92	257		2,614	1,197	248	20				.356	.513	.935	596	171	.433	136	161.5
23	Jimmie Foxx J. Foxx	.421	656	2,165	461	710	126	48	116	498	344	5	281	26		2,567	1,280	290	53				.328	.591	1.012	547	213.9	.448	155	192.8
24	Juan Soto J. Soto	.421	936	3,280	655	934	179	15	201	592	769	16	696	57	23	4,087	1,746	395	2	20	67	84	.285	.532	.953	790	299.8	.404	158	290.5
25	Max Bishop M. Bishop	.421	820	2,822	598	757	139	26	25	227	718	25	276	31		3,635	1,023	190	70				.268	.363	.783	559	94.2	.381	111	56