The average ring size for an adult woman is L to Q (6 to 8), while the average size for an adult man is J to W (9 to 11). The best size is usually a ring with a snug fit that gives a little resistance when you take it off. Wider rings should be worn looser than narrow rings.

You may like to print out our ring-size guide. To use it, place a ring you already own over the printed copy to determine what size it is.

The chart below shows sizes using different international systems. The "Wheat Sheaf" system used in Australia is also used in Ireland and the UK. You can wrap a piece of string around your finger and then measure the length of the string to compare to the circumference (circ.) sizes in the chart.

Inside Diameter (in)	Inside Diameter (mm)	Inside Circ. (in)	Inside Circ. (mm)	US/Canada	Australia	Japan	Switzerland
0.474	12.0	1.488	37.8	1/2	A
0.482	12.2	1.513	38.4	3/4	A 1/2
0.490	12.4	1.539	39.1	1	B	1
0.498	12.6	1.564	39.7	1 1/4	B 1/2
0.506	12.9	1.589	40.4	1 1/2	C
0.514	13.1	1.614	41.0	1 3/4	C 1/2
0.522	13.3	1.639	41.6	2	D	2	1.50
0.530	13.5	1.664	42.3	2 1/4	D 1/2
0.538	13.7	1.689	42.9	2 1/2	E	3	2.75
0.546	13.9	1.714	43.5	2 3/4	E 1/2
0.554	14.1	1.740	44.2	3	F	4	4.00
0.562	14.3	1.765	44.8	3 1/4	F 1/2	5	5.25
0.570	14.5	1.790	45.5	3 1/2	G
0.578	14.7	1.815	46.1	3 3/4	G 1/2	6	6.50
0.586	14.9	1.840	46.7	4	H	7
0.594	15.1	1.865	47.4	4 1/4	H 1/2		7.75
0.602	15.3	1.890	48.0	4 1/2	I	8
0.610	15.5	1.915	48.7	4 3/4	J		9.00
0.618	15.7	1.941	49.3	5	J 1/2	9
0.626	15.9	1.966	49.9	5 1/4	K		10.00
0.634	16.1	1.991	50.6	5 1/2	K 1/2	10
0.642	16.3	2.016	51.2	5 3/4	L		11.75
0.650	16.5	2.041	51.8	6	L 1/2	11	12.75
0.658	16.7	2.066	52.5	6 1/4	M	12
0.666	16.9	2.091	53.1	6 1/2	M 1/2	13	14.00
0.674	17.1	2.116	53.8	6 3/4	N
0.682	17.3	2.141	54.4	7	N 1/2	14	15.25
0.690	17.5	2.167	55.0	7 1/4	O
0.698	17.7	2.192	55.7	7 1/2	O 1/2	15	16.50
0.706	17.9	2.217	56.3	7 3/4	P
0.714	18.1	2.242	56.9	8	P 1/2	16	17.75
0.722	18.3	2.267	57.6	8 1/4	Q
0.730	18.5	2.292	58.2	8 1/2	Q 1/2	17
0.738	18.7	2.317	58.9	8 3/4	R		19
0.746	18.9	2.342	59.5	9	R 1/2	18
0.754	19.2	2.368	60.1	9 1/4	S		20.25
0.762	19.4	2.393	60.8	9 1/2	S 1/2	19
0.770	19.6	2.418	61.4	9 3/4	T		21.5
0.778	19.8	2.443	62.1	10	T 1/2	20
0.786	20.0	2.468	62.7	10 1/4	U	21
0.794	20.2	2.493	63.3	10 1/2	U 1/2	22	22.75
0.802	20.4	2.518	64.0	10 3/4	V
0.810	20.6	2.543	64.6	11	V 1/2	23
0.818	20.8	2.569	65.2	11 1/4	W		25
0.826	21.0	2.594	65.9	11 1/2	W 1/2	24
0.834	21.2	2.619	66.5	11 3/4	X
0.842	21.4	2.644	67.2	12	X 1/2	25	27.50
0.850	21.6	2.669	67.8	12 1/4	Y
0.858	21.8	2.694	68.4	12 1/2	Z	26	28.75
0.866	22.0	2.719	69.1	12 3/4	Z 1/2
0.874	22.2	2.744	69.7	13		27
0.882	22.4	2.769	70.3	13 1/4	Z1
0.890	22.6	2.795	71.0	13 1/2
0.898	22.8	2.820	71.6	13 3/4	Z2
0.906	23.0	2.845	72.3	14	Z3
0.914	23.2	2.870	72.9	14 1/4
0.922	23.4	2.895	73.5	14 1/2	Z4