30 homers, age 37 and older

Those parameters seemed to provide a sweet spot of information.  It's been done 39 times, including multiple times by some players.  Two more players may do it this season: Alex Rodriguez and David Ortiz, who has already done it twice and who needs five more homers to reach 500 for his career.  Age is determined before July 1.  So Rodriguez is considered 39 by baseball-reference.com even though he turned 40 in July.

35 homers by players at least 37 years old has been reached 20 times.

40 homers by players at least 37 years old has been reached 10 times, including all three times Bonds made the list of 39 when he hit 46 and 45 twice.

Aaron is the only other player to hit at least 30 homers three times at ages 37 or older.  Both Aaron and Bonds did it at ages 37,38,39.  These players hit at least 30 twice at ages 37 or older: Ruth, Darrell Evans, Ortiz, McGriff, Palmeiro.

Aaron has the top: 47 at age 37 in 1971.  Aaron also has the biggest gap between homers and age: 10.  Also the biggest percentage difference: 27%.

The complete list is below sorted by homers.

Darrell Evans is the only 40 year old to hit at least 30 homers: 34 in 1987.  Evans is one of two to lead his league in homers: 40 in AL in 1985 at age 38; Fisk was second with 37 at age 37.  Dale Murphy, 29 years old, led the NL in 1985 with 37.  Cy Williams led the NL with 30 homers in 1927 at age 39; he was also the first to hit at least 30 at 37 or older.  Next was Ruth twice, then Sauer in 1954: 41 for the Cubs at 37.

Some matched their age, including Ted Williams: 38 in 1958, Fisk 37 in 1985, Palmeiro 38 in 2003, Martinez 37 in 2000.

Leading his league:
Edgar Martinez: RBI (Aaron low: 77)
BB: Ruth both times, Bonds all three
HBP: Baylor, Giambi
BA: Ted Williams, Bonds twice (Kingman low: .210)
OBP: Bonds all three, Ruth, Ted Williams (Kingman low: .255)
SLG: Bonds all three, Aaron, Ted Williams (Kingman low: .431)
OPS: Bonds all three, Aaron, Ted Williams (Kingman low: .686)

Rk	Player	HR	Year	Age	Tm	Lg	G	PA	AB	R	H	2B	3B	RBI	BB	IBB	SO	HBP	SH	SF	GDP	SB	CS	BA	OBP	SLG	OPS	Pos
1	Hank Aaron	47	1971	37	ATL	NL	139	573	495	95	162	22	3	118	71	21	58	2	0	5	9	1	1	.327	.410	.669	1.079	*39H
2	Barry Bonds	46	2002	37	SFG	NL	143	612	403	117	149	31	2	110	198	68	47	9	0	2	4	9	2	.370	.582	.799	1.381	*7/DH
3	Barry Bonds	45	2004	39	SFG	NL	147	617	373	129	135	27	3	101	232	120	41	9	0	3	5	6	1	.362	.609	.812	1.422	*7/HD
4	Barry Bonds	45	2003	38	SFG	NL	130	550	390	111	133	22	1	90	148	61	58	10	0	2	7	7	0	.341	.529	.749	1.278	*7/DH
5	Andres Galarraga	44	1998	37	ATL	NL	153	648	555	103	169	27	1	121	63	11	146	25	0	5	8	7	6	.305	.397	.595	.991	*3/HD
6	Rafael Palmeiro	43	2002	37	TEX	AL	155	663	546	99	149	34	0	105	104	16	94	6	0	7	10	2	0	.273	.391	.571	.962	*3D/H
7	Hank Sauer	41	1954	37	CHC	NL	142	606	520	98	150	18	1	103	70		68	6	2	7	8	2	1	.288	.375	.563	.938	*97/H
8	Babe Ruth	41	1932	37	NYY	AL	133	589	457	120	156	13	5	137	130		62	2	0			2	2	.341	.489	.661	1.150	*97/H3
9	Darrell Evans	40	1985	38	DET	AL	151	594	505	81	125	17	0	94	85	12	85	1	1	2	5	0	4	.248	.356	.519	.875	*3DH/5
10	Hank Aaron	40	1973	39	ATL	NL	120	465	392	84	118	12	1	96	68	13	51	1	0	4	7	1	1	.301	.402	.643	1.045	*79H
11	Frank Thomas	39	2006	38	OAK	AL	137	559	466	77	126	11	0	114	81	3	81	6	0	6	13	0	0	.270	.381	.545	.926	*D/H
12	Moises Alou	39	2004	37	CHC	NL	155	675	601	106	176	36	3	106	68	2	80	0	0	6	12	3	0	.293	.361	.557	.919	*7/HD
13	Rafael Palmeiro	38	2003	38	TEX	AL	154	654	561	92	146	21	2	112	84	9	77	5	0	4	7	2	0	.260	.359	.508	.867	*D3/H
14	Ted Williams	38	1957	38	BOS	AL	132	547	420	96	163	28	1	87	119	33	43	5	0	2	11	0	1	.388	.526	.731	1.257	*7/H
15	Edgar Martinez	37	2000	37	SEA	AL	153	665	556	100	180	31	0	145	96	8	95	5	0	8	13	3	0	.324	.423	.579	1.002	*D/H3
16	Carlton Fisk	37	1985	37	CHW	AL	153	620	543	85	129	23	1	107	52	12	81	17	2	6	9	17	9	.238	.320	.488	.808	*2D/H
17	Steve Finley	36	2004	39	TOT	NL	162	706	628	92	170	28	1	94	61	1	82	1	9	7	14	9	7	.271	.333	.490	.823	*8/HD
18	David Ortiz	35	2014	38	BOS	AL	142	602	518	59	136	27	0	104	75	22	95	3	0	6	18	0	0	.263	.355	.517	.873	*D/H3
19	Mike Schmidt	35	1987	37	PHI	NL	147	613	522	88	153	28	0	113	83	15	80	2	0	6	17	2	1	.293	.388	.548	.936	*5/3H6
20	Dave Kingman	35	1986	37	OAK	AL	144	604	561	70	118	19	0	94	33	3	126	3	0	7	16	3	3	.210	.255	.431	.686	*D/3H
21	Alfonso Soriano	34	2013	37	TOT	ML	151	626	581	84	148	32	1	101	36	3	156	5	0	4	11	18	9	.255	.302	.489	.791	*7D/H
22	Raul Ibanez	34	2009	37	PHI	NL	134	565	500	93	136	32	3	93	56	8	119	4	0	5	16	4	0	.272	.347	.552	.899	*7/HD
23	Jim Thome	34	2008	37	CHW	AL	149	602	503	93	123	28	0	90	91	9	147	4	0	4	17	1	0	.245	.362	.503	.865	*DH
24	Darrell Evans	34	1987	40	DET	AL	150	609	499	90	128	20	0	99	100	8	84	2	2	6	2	6	5	.257	.379	.501	.880	*3DH/5
25	Hank Aaron	34	1972	38	ATL	NL	129	545	449	75	119	10	0	77	92	15	55	1	0	2	17	4	0	.265	.390	.514	.904	*39/H
Rk	Player	HR	Year	Age	Tm	Lg	G	PA	AB	R	H	2B	3B	RBI	BB	IBB	SO	HBP	SH	SF	GDP	SB	CS	BA	OBP	SLG	OPS	Pos
26	Babe Ruth	34	1933	38	NYY	AL	137	576	459	97	138	21	3	104	114		90	2	0			4	5	.301	.442	.582	1.023	*97/H13
27	Jason Giambi	32	2008	37	NYY	AL	145	565	458	68	113	19	1	96	76	5	111	22	0	9	6	2	1	.247	.373	.502	.876	*3D/H
28	Ellis Burks	32	2002	37	CLE	AL	138	570	518	92	156	28	0	91	44	3	108	6	1	1	13	2	3	.301	.362	.541	.903	*D/7H
29	Willie Stargell	32	1979	39	PIT	NL	126	480	424	60	119	19	0	82	47	12	105	3	0	6	10	0	1	.281	.352	.552	.904	*3H
30	Ernie Banks	32	1968	37	CHC	NL	150	595	552	71	136	27	0	83	27	4	67	5	9	2	12	2	0	.246	.287	.469	.756	*3/H
31	Fred McGriff	31	2001	37	TOT	ML	146	586	513	67	157	25	2	102	66	13	106	3	0	4	13	1	2	.306	.386	.544	.930	*3D/H
32	Don Baylor	31	1986	37	BOS	AL	160	687	585	93	139	23	1	94	62	8	111	35	0	5	12	3	5	.238	.344	.439	.783	*D3/7H
33	Rico Carty	31	1978	38	TOT	AL	145	593	528	70	149	21	1	99	57	7	57	0	1	7	15	1	1	.282	.348	.502	.850	*D/H
34	David Ortiz	30	2013	37	BOS	AL	137	600	518	84	160	38	2	103	76	27	88	1	0	5	21	4	0	.309	.395	.564	.959	*D/3H
35	Ken Griffey	30	2007	37	CIN	NL	144	623	528	78	146	24	1	93	85	14	99	1	0	9	14	6	1	.277	.372	.496	.869	*9/HD
36	Fred McGriff	30	2002	38	CHC	NL	146	595	523	67	143	27	2	103	63	6	99	4	0	5	13	1	2	.273	.353	.505	.858	*3/HD
37	Chili Davis	30	1997	37	KCR	AL	140	567	477	71	133	20	0	90	85	16	96	1	0	4	15	6	3	.279	.386	.509	.896	*D/H
38	Frank Robinson	30	1973	37	CAL	AL	147	630	534	85	142	29	0	97	82	12	93	10	1	3	13	1	1	.266	.372	.489	.861	*D7/H
39	Cy Williams	30	1927	39	PHI	NL	131	569	492	86	135	18	2	98	61		57	9	8			0		.274	.365	.502	.867	*9/H

Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 9/1/2015.

Complimentary post:

30 homers, age 22 or younger Wednesday, September 2, 2015