International Conversion Chart For Ring Sizes

In order to help users in understanding Ring sizes and parameters used in different countries, we have pulled out this chart to assist you in doing so. The chart includes inner diameter as well as circumference of a ring in inches and millimetres.

The Ring sizes are measured using simple tools such as Ring sizer stick (or Ring Mandrel) and Ring finger sizer as shown in the images below.

The size parameters differ country wise as shown in the table below.

Conversion chart for ring sizes
Inside diameter		Inside circumference		Sizes
(in)	(mm)	(in)	(mm)	US, Canada and Mexico	UK, Ireland, Australia and New Zealand	China, Japan, South America	India	Italy, Spain, Netherlands, Switzerland
0.458	11.63	1.44	36.5	0
0.466	11.84	1.46	37.2	¼
0.474	12.04	1.49	37.8	½	A
0.482	12.24	1.51	38.5	¾	A½
0.49	12.45	1.54	39.1	1	B	1
0.498	12.65	1.56	39.7	1¼	B½
0.506	12.85	1.59	40.4	1½	C			0.5
0.514	13.06	1.61	41	1¾	C½		1	1
0.522	13.26	1.64	41.7	2	D	2	2	1.75
0.53	13.46	1.67	42.3	2¼	D½			2.25
0.538	13.67	1.69	42.9	2½	E	3	3	3
0.546	13.87	1.72	43.6	2¾	E½		4	3.5
0.554	14.07	1.74	44.2	3	F	4		4.25
0.562	14.27	1.77	44.8	3¼	F½	5	5	4.75
0.57	14.48	1.79	45.5	3½	G			5.5
0.578	14.68	1.82	46.1	3¾	G½	6	6	6
0.586	14.88	1.84	46.8	4	H	7		6.75
0.594	15.09	1.87	47.4	4¼	H½		7	7.5
0.602	15.29	1.89	48	4½	I	8	8	8
0.61	15.49	1.92	48.7	4¾	J		9	8.75
0.618	15.7	1.94	49.3	5	J½	9		9.25
0.626	15.9	1.97	50	5¼	K		10	10
0.634	16.1	1.99	50.6	5½	K½	10		10.5
0.642	16.31	2.02	51.2	5¾	L		11	11.25
0.65	16.51	2.04	51.9	6	L½	11	12	11.75
0.658	16.71	2.07	52.5	6¼	M	12		12.5
0.666	16.92	2.09	53.1	6½	M½	13	13	13.25
0.674	17.12	2.12	53.8	6¾	N			13.75
0.682	17.32	2.14	54.4	7	N½	14	14	14.5
0.69	17.53	2.17	55.1	7¼	O		15	15
0.698	17.73	2.19	55.7	7½	O½	15		15.75
0.706	17.93	2.22	56.3	7¾	P		16	16.25
0.714	18.14	2.24	57	8	P½	16	17	17
0.722	18.34	2.27	57.6	8¼	Q			17.5
0.73	18.54	2.29	58.3	8½	Q½	17	18	18.25
0.738	18.75	2.32	58.9	8¾	R		19	19
0.746	18.95	2.34	59.5	9	R½	18		19.5
0.754	19.15	2.37	60.2	9¼	S		20	20.25
0.762	19.35	2.39	60.8	9½	S½	19	21	20.75
0.77	19.56	2.42	61.4	9¾	T			21.5
0.778	19.76	2.44	62.1	10	T½	20	22	22
0.786	19.96	2.47	62.7	10¼	U	21	23	22.75
0.794	20.17	2.49	63.4	10½	U½	22		23.25
0.802	20.37	2.52	64	10¾	V		24	24
0.81	20.57	2.54	64.6	11	V½	23	25	24.75
0.818	20.78	2.57	65.3	11¼	W			25.25
0.826	20.98	2.59	65.9	11½	W½	24	26	26
0.834	21.18	2.62	66.6	11¾	X			26.5
0.842	21.39	2.65	67.2	12	X½	25	27	27.25
0.85	21.59	2.67	67.8	12¼	Y		28	27.75
0.858	21.79	2.7	68.5	12½	Z	26		28.5
0.866	22	2.72	69.1	12¾	Z½		29	29
0.874	22.2	2.75	69.7	13		27	30	29.75
0.882	22.4	2.77	70.4	13¼	Z1			30.5
0.89	22.61	2.8	71	13½			31	31
0.898	22.81	2.82	71.7	13¾	Z2		32	31.75
0.906	23.01	2.85	72.3	14	Z3			32.25
0.914	23.22	2.87	72.9	14¼			33	33
0.922	23.42	2.9	73.6	14½	Z4			33.5
0.93	23.62	2.92	74.2	14¾			34	34.25
0.938	23.83	2.95	74.8	15			35	34.75
0.946	24.03	2.97	75.5	15¼				35.5
0.954	24.23	3	76.1	15½			36	36.25
0.962	24.43	3.02	76.8	15¾				36.75
0.97	24.64	3.05	77.4	16			37	37.5

Ring sizes can be measured physically by a plastic or metal ring sizer, or by measuring the girth of a ring that already fits. There are also online measuring tools available, though they may not be as precise as checking for the size physically.

The circumference of the ring (inner circle) is the distance around it. It is calculated based on the formula, π × diameter (where π=3.14). For example, the Indian size 10 has a diameter 15.9 mm. Hence the circumference would be 3.14 x 15.9 = Approx. 50 mm.

The average ring size for women in India is around Size 13-14 and for men, it is between Size 16-18.

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