International Ring Size Converter

MARCHÉ
NOIR		 U.S.
/ CDN.		 DIAMETER
( in millimetres ) 		U.K. JAPANESE CIRCUMFERENCE
( in millimetres )
 
4
14.8mm
H 1/2
7
46.5mm
 
4 1/2
15.2mm
I 1/2
8
48mm
XS
5
15.6mm
J 1/2
9
49mm
 
5 1/2
16mm
L
10
50.5mm
 
6
16.4mm
M
12
52mm
S
6 1/2
16.8mm
N
13
53mm
 
7
17.3mm
O
14
54.5mm
 
7 1/2
17.7mm
P
15
55.5mm
M
8
18.1mm
Q
16
57mm
 
8 1/2
18.5mm
Q 1/2
17
58mm
 
9
18.9mm
R 1/2
18
59.5mm
L
9 1/2
19.3mm
S 1/2
20
61mm
 
10
19.7mm
T 1/2
21
62mm
 
10 1/2
20.1mm
U 1/2
22
63.5mm
XL
11
20.6mm
V 1/2
24
64.5mm
 
11 1/2
21mm
W 1/2
25
66mm
 
12
21.4mm
Y
26
67.5mm
XXL
12 1/2
21.8mm
Z
27
68.5mm
 
13
22.2mm
Z+1
28
70mm
 
13 1/2
22.6mm
Z+2
29
71mm
XXXL
14
23mm
Z+3
31
72.5mm
 
14 1/2
23.4mm
Z+4
32
74mm
 
15
23.9mm
Z+5
33
75mm