Ring size guide

UK, Australia,
New Zealand,
Ireland
USA, Canada Europe Inner Diameter
(mm)
F 1/2 3.00 44.2 14.1
G 3.25 44.8 14.3
G 1/2 3.50 45.5 14.5
H 3.75 46.1 14.7
H 1/2 4.00 46.8 14.9
I 4.25 47.4 15.1
I 1/2 4.50 48.0 15.3
J 4.75 48.7 15.5
J 1/2 5.00 49.3 15.7
K 5.25 50.0 15.9
K 1/2 5.50 50.6 16.1
L 5.75 51.2 16.3
L 1/2 6.00 51.9 16.5
M 6.25 52.5 16.7
M 1/2 6.50 53.1 16.9
N 6.75 53.8 17.1
N 1/2 7.00 54.4 17.3
O 7.25 55.1 17.5
O 1/2 7.50 55.7 17.7
P 7.75 56.3 17.9
P 1/2 8.00 57.0 18.1
Q 8.25 57.6 18.3
Q 1/2 8.50 58.3 18.5
R 8.75 58.9 18.8
R 1/2 9.00 59.7 19.0
S 9.25 60.2 19.2
S 1/2 9.50 60.8 19.4
T 9.75 61.4 19.6
T 1/2 10.00 62.1 19.8
U 10.25 62.7 20.0
U 1/2 10.50 63.4 20.2
V 10.75 64.0 20.4
V 1/2 11.00 64.6 20.6