International Ring Size Equivalents

Metric

Continental
Japanese

English

American

37.8252

-

A

1/2

38.4237

-

A 1/2

3/4

39.0222

-

B

1

39.6207

-

B 1/2

1 1/4

40.2192

-

C

1 1/2

40.8177

-

C 1/2

1 3/4

41.4162

1

D

2

42.0147

2

D 1/2

2 1/4

42.6132

-

E

2 1/2

43.2117

3

E 1/2

2 3/4

43.8102

4

F

3

44.4087

-

F 1/2

3 1/4

45.0072

5

G

3 1/4

45.6057

-

G 1/2

3 1/2

46.2042

6

H

3 3/4

46.8027

-

H 1/2

4

47.4012

7

I

4 1/4

47.9997

8

I 1/2

4 1/2

48.5982

-

J

4 3/4

49.1967

9

J 1/2

5

49.7952

10

K

5 1/4

50.3937

-

K 1/2

5 1/2

50.9922

11

L

5 3/4

51.5907

-

L 1/2

6

52.1892

12

M

6 1/4

52.7877

13

M 1/2

6 1/2

53.4660

-

N

6 3/4

54.1044

14

N 1/2

7

54.7428

15

O

7

55.3812

-

O 1/2

7 1/4

56.0196

16

P

7 1/2

56.6580

-

P 1/2

7 3/4

57.2964

17

Q

8

57.9348

18

Q 1/2

8 1/4

58.5732

-

R

8 1/2

59.2116

19

R 1/2

8 3/4

59.8500

20

S

9

60.4884

-

S 1/2

9 1/4

61.1268

21

T

9 1/2

61.7652

22

T 1/2

9 3/4

62.4026

-

U

10

63.0420

23

U 1/2

10 1/4

63.6804

24

V

10 1/2

64.3188

-

V 1/2

10 3/4

64.8774

25

W

11

65.4759

-

W 1/2

11 1/4

66.0744

26

X

11 1/2

66.6729

-

X 1/2

11 3/4

67.2714

-

Y

12

67.8699

-

Y 1/2

12 1/4

68.4684

-

Z

12 1/2