Ring Size Conversion

UK      

     US

EU    

Inside 

Diameter

C 1 1/2 40 1/2 12.85
D 2 41 1/2 13.06
E 2 1/2 42 3/4 13.67
F 3 44 1/2 14.07
G 3 1/2 45 1/2 14.48
H 4 46 1/2 14.88
I 4 1/2 47 3/4 15.29
J 4 3/4 49 1/2 15.50
K 5 1/4 50 1/4 15.90
L 5 3/4 51 1/2 16.30
M 6 1/4 52 1/2 16.70
N 6 3/4 54  17.10
O 7 1/4 55 1/4 17.50
P 7 3/4 56 1/4 17.90
Q 8 1/4 57 1/2 18.30
R 8 3/4 58 1/2 18.80
S 9 1/4 60 1/4 19.20
T 9 3/4 61 1/2 19.60
U 10 1/4 62 1/2 20
V 10 3/4 63 3/4 20.4
W 11 1/4 65 1/4 20.80
X 11 3/4 66 1/4 21.20
Y 12 1/4 67 1/2 21.60
Z 12 1/2 68 3/4 21.80