Ring Conversion For International Sizes

US Size	Dia. -inch	Dia. in MM	Metric -MM	British	French	German	Japanese	Swiss
4	.585	14.86	46.5	H 1/2	-	15	7
4 1/4	-	15.04	47.1	I	47 3/4			7 3/4
4 1/2	.601	15.27	47.8	I 1/2	-	15 1/4	8
4 5/8	-	15.40	48.1	J	49	15 1/2		9
4 3/4	-	15.53	48.4	-	-
5	.618	15.70	49.0	J 1/2	-	15 3/4	9
5 1/8	-	15.80	49.3	K	50			10
5 1/4	-	15.90	49.6	-	-
5 3/8	-	16.0	50.0	K 1/2	-		10
5 1/2	.634	16.10	50.3	L	51 3/4	16		11 3/4
5 3/4	-	16.30	50.9	-	-
5 7/8	-	16.41	51.3	L 1/2	-
6	.650	16.51	51.5	M	52 3/4	16 1/2	12	12 3/4
6 1/4	-	16.71	52.2	M 1/2	-
6 1/2	.666	16.92	52.8	N	54	17	13	14
6 3/4	-	17.13	53.4	N 1/2	-
7	.683	17.35	54.0	O	55 1/4	17 1/4	14	15 1/4
7 1/4	-	17.45	54.7	O 1/2	-
7 1/2	.699	17.75	55.3	P	56 1/2	17 3/4	15	16 1/2
7 3/4	-	17.97	55.9	P 1/2	-
8	.716	18.19	56.6	Q	57 3/4	18	16	17 3/4
8 1/4	-	18.35	57.2	Q 1/2	-
8 1/2	.732	18.53	57.8	-	-	18 1/2	17
8 5/8	-	18.61	58.4	R	59			19
8 3/4	-	18.69	58.4	-	-
8 7/8	-	18.80	59.0	R 1/2	-
9	.748	18.89	59.1	-	-	19	18
9 1/8	-	19.10	59.4	S	60 1/4			20 1/4
9 1/4	-	19.22	59.7	-	-
9 3/8	-	19.31	60.0	S 1/2	-
9 1/2	.764	19.41	60.3	-	-	19 1/2	19
9 5/8	-	19.51	60.6	T	61 1/2			21 1/2
9 3/4	-	19.62	60.9	-	-
10	.781	19.84	61.6	T 1/2	-	20	20
10 1/4	-	20.02	62.2	U	62 3/4		21	22 3/4
10 1/2	.797	20.20	62.8	U 1/2	-	20 1/4	22
10 5/8	-	20.32	63.1	V	63			23 3/4
10 3/4	-	20.44	63.5	-	-
11	.814	20.68	64.1	V 1/2	-	20 3/4	23
11 1/8	-	20.76	64.3	W	65			25
11 1/4	-	20.85	64.7	-	-
11 3/8	-	20.94	65.0	W 1/2	-
11 1/2	-	21.08	65.3	-	-	21	24
11 5/8	.830	21.18	65.7	X	66 1/4			26 1/4
11 3/4	-	21.24	66.0	-	-
11 7/8	-	21.30	66.3	X 1/2	-
12	.846	21.49	66.6	Y	67 1/2	21 1/4	25	27 1/2
12 1/4	-	21.69	67.2	Y 1/2	-
12 1/2	.862	21.89	67.9	Z	68 3/4	21 3/4	26	28 3/4
12 3/4	-	22.10	68.5	Z 1/2	-
13	.879	22.33	69.1	-	-	22	27