M

M

Reference chart for ring size conversions

Use this chart to convert your ring size for ordering. You can calculate the size in US, inch, millimeter, that is also listed for your conviencience  

US  Size
Dia. -inch
Dia. in MM
Metric -MM
British 
French 
German 
Japanese 
Swiss 
0000
.390
9.91
  
-
        
00
.422
10.72
  
-
        
0
.454
11.53
  
-
        
1/2
.474
11.95
  
A
        
3/4
.482
12.18
  
A 1/2
        
1
.487
12.37
38.9
B
    
1
  
1 1/4
-
12.60
39.6
B 1/2
        
1 1/2
.503
12.78
40.2
C
        
1 3/4
-
13.00
40.8
C 1/2
        
2
.520
13.21
41.5
D
41 1/2
13 1/2
2
1 1/2
2 1/4
-
13.41
42.1
D 1/2
-
-
    
2 1/2
.536
13.61
42.7
E
42 3/4
13 3/4
3
2 3/4
2 3/4
-
13.83
43.4
E 1/2
-
-
    
3
.553
14.05
44.0
F
44
14
4
4
3 1/8
-
14.15
44.3
F 1/2
-
-
    
3 1/4
-
14.25
44.6
-
-
-
    
3 3/8
-
14.36
44.9
G
45 1/4
-
5
5 1/4
3 1/2
.569
14.45
45.2
-
-
14 1/2
    
3 5/8
-
14.56
45.6
 G 1/2
-
  
6
  
3 3/4
-
14.65
45.9
H
46 1/2
    
6 1/2
4
.585
14.86
46.5
H 1/2
-
15
7
  
4 1/4
-
15.04
47.1
I 
47 3/4
    
7 3/4
4 1/2
.601
15.27
47.8
I 1/2
-
15 1/4
8
  
4 5/8
-
15.40
48.1
J
49
15 1/2
  
9
4 3/4
-
15.53
48.4
-
-
      
5
.618
15.70
49.0
J 1/2
-
15 3/4
9
  
5 1/8
-
15.80
49.3
K
50
    
10
5 1/4
-
15.90
49.6
-
-
      
5 3/8
-
16.0
50.0
K 1/2
-
  
10
  
5 1/2
.634
16.10
50.3
L
51 3/4
16
  
11 3/4
5 3/4
-
16.30
50.9
-
-
      
5 7/8
-
16.41
51.3
L 1/2
-
      
6
.650
16.51
51.5
M
52 3/4
16 1/2
12
12 3/4
6 1/4
-
16.71
52.2
M 1/2
-
      
6 1/2
.666
16.92
52.8
N
54
17
13
14
6 3/4
-
17.13
53.4
N 1/2
-
      
7
.683
17.35
54.0
O
55 1/4
17 1/4
14
15 1/4
7 1/4
-
17.45
54.7
O 1/2
-
      
7 1/2
.699
17.75
55.3
P
56 1/2
17 3/4
15
16 1/2
7 3/4
-
17.97
55.9
P 1/2
-
      
8
.716
18.19
56.6
Q
57 3/4
18
16
17 3/4
8 1/4
-
18.35
57.2
Q 1/2
-
      
8 1/2
.732
18.53
57.8
-
-
18 1/2
17
  
8 5/8
-
18.61
58.4
R
59
    
19
8 3/4
-
18.69
58.4
-
-
      
8 7/8
-
18.80
59.0
R 1/2
-
      
9
.748
18.89
59.1
-
-
19
18
  
9 1/8
-
19.10
59.4
S
60 1/4
    
20 1/4
9 1/4
-
19.22
59.7
-
-
      
9 3/8
-
19.31
60.0
S 1/2
-
      
9 1/2
.764
19.41
60.3
-
-
19 1/2
19
  
9 5/8
-
19.51
60.6
T
61 1/2
    
21 1/2
9 3/4
-
19.62
60.9
-
-
      
10
.781
19.84
61.6
T 1/2
-
20
20
  
10 1/4
-
20.02
62.2
U
62 3/4
  
21
22 3/4
10 1/2
.797
20.20
62.8
U 1/2
-
20 1/4
22
  
10 5/8
-
20.32
63.1
V
63
    
23 3/4
10 3/4
-
20.44
63.5
-
-
      
11
.814
20.68
64.1
V 1/2
-
20 3/4
23
  
11 1/8
-
20.76
64.3
W
65
    
25
11 1/4
-
20.85
64.7
-
-
      
11 3/8
-
20.94
65.0
W 1/2
-
      
11 1/2
-
21.08
65.3
-
-
21
24
  
11 5/8
.830
21.18
65.7
X
66 1/4
    
26 1/4
11 3/4
-
21.24
66.0
-
-
      
11 7/8
-
21.30
66.3
X 1/2
-
      
12
.846
21.49
66.6
Y
67 1/2
21 1/4
25
27 1/2
12 1/4
-
21.69
67.2
Y 1/2
-
      
12 1/2
.862
21.89
67.9
Z
68 3/4
21 3/4
26
28 3/4
12 3/4
-
22.10
68.5
Z 1/2
-
      
13
.879
22.33
69.1
-
-
22
27
  
13