To help you determine your ring size, please refer to the ring conversion chart below.
The 'inch' & 'mm' sizes are the inner circumference of the ring.

INTERNATIONAL RING CONVERSION CHART
Size
(inches)*
 Size
(mm)
Diameter
(mm)
 U.K. size
 U.S size
 7/8 48
15.27
I 1/2
 4 1/2
1 15/16
49
15.7
J 1/2
5
2
51
16.1
L
 5 1/2
2 1/16
 52
 16.51
 M
 6
2 1/8
 53
 16.92
 N
 6 1/2
2 3/16
 55
 17.35
 O
 7
2 1/4
 56
 17.75
 P
 7 1/2
2 5/16
 57
 18.19
 Q
 8
2 3/8
 58
 18.53
 Q 1/2
 8 1/2
2 7/16
 59
 18.89
 R 1/2
 9
2 1/2
 61
 19.41
 S 1/2
 9 1/2
2 9/16
 62
 19.84
 T 1/2
 10
2 5/8
 63
 20.2
 U 1/2
 10 1/2
2 11/16
 65
 20.68
 V 1/2
 11
2 3/4
 66
 21.08
 W 1/2
 11 1/2
2 13/16
 68
 21.49
 Y
 12
2 7/8
 69
 21.89
 Z
 12 1/2
2 5/16
 70
 22.33
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