Diamonds • Precious Gemstones • Jewelry • Gemology

US, British & European Ring Sizes

The most common sizes for women are 6 and 7, and for men 10 and 11
US	British	European
3	F	44
	F½	45
3½	G
4	H	46
4½	H½	47
	I	48
5	J	49
	J½	50
5½	K
	K½	51
6	L
		52
	L½
6½	M
		53
	M½
7	N	54
	N½
		55
7½	O
	O½
		56
8	P
		57
	P½
	Q
8½		58
	Q½
	R	59
9
	R½
		60
	S
9½
	S½
		61
	T
10	T½	62
	U
		63
10½	U½
	V	64
	V½
11
	W	65
	W½
11½		66
	X
	X½
		67
12
	Y
		68
	Y½
12½
	Z	69
	Z½
13
		70
The US uses a numeric system from 1-13, UK has an alphabetic system from A-Z and the European system is numeric from 38-70 = interior circumference in millimeters. Sizes within 0.01mm have been equated.