Reference Database

International Ring Size Chart.

Compare sizing systems from the US & Canada, UK & Australia, Europe (ISO), and Asia by physical dimensions. Click any row to preview the sizing target or print for physical matching.

Go to Screen Sizer

US & Canada	UK & Australia	Europe (ISO)	Asia (IN/JP/CN)	Diameter (mm)	Circumference (mm)
3	F	44 mm	Size 4	14.10 mm	44.30 mm
3.5	G	45 mm	Size 5	14.50 mm	45.55 mm
4	H	47 mm	Size 7	14.90 mm	46.81 mm
4.5	I	48 mm	Size 8	15.30 mm	48.07 mm
5	J½	49 mm	Size 9	15.70 mm	49.32 mm
5.5	K½	51 mm	Size 10	16.10 mm	50.58 mm
6	L½	52 mm	Size 11.5	16.50 mm	51.84 mm
6.5	M½	53 mm	Size 13	16.90 mm	53.09 mm
7	O	54 mm	Size 14	17.30 mm	54.35 mm
7.5	P	56 mm	Size 15	17.70 mm	55.61 mm
8	Q	57 mm	Size 16	18.10 mm	56.86 mm
8.5	Q½	58 mm	Size 17	18.50 mm	58.12 mm
9	R½	59 mm	Size 18	18.90 mm	59.38 mm
9.5	S½	60 mm	Size 19.5	19.30 mm	60.63 mm
10	T½	62 mm	Size 21	19.80 mm	62.20 mm
10.5	U½	63 mm	Size 22	20.20 mm	63.46 mm
11	V½	65 mm	Size 23.5	20.60 mm	64.72 mm
11.5	W½	66 mm	Size 25	21.00 mm	65.97 mm
12	Y	67 mm	Size 26	21.40 mm	67.23 mm
12.5	Z	68 mm	Size 27	21.80 mm	68.49 mm
13	Z+1	70 mm	Size 28	22.20 mm	69.74 mm
13.5	Z+2	71 mm	Size 29	22.60 mm	71.00 mm

Interactive Matcher

Visual Scale Preview.

SELECTED US SIZE:7

INNER DIAMETER:17.30 mm

CIRCUMFERENCE:54.35 mm

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