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International Ring Finger Sizes

Finger Sizes
We get asked about finger size conversions quite frequently, and we have never seen a chart which lists British, European, Japanese, and American systems side by side, so we created our own!
If you wish to order a ring from us, please feel free to specify the finger size in any of these systems.
Diameter = Internal diameter in millimetres.
Circumference = Internal circumference in millimetres.

Britain	Europe	Japan	USA	Diameter	Circumference
			0	11.54	36.25
A				11.90	37.38
		0		12.00	37.70
A¹/₂				12.10	38.01
B				12.30	38.64
			1	12.37	38.86
B¹/₂				12.50	39.27
			1¹/₄	12.58	39.52
C				12.70	39.90
	0.15		1¹/₂	12.78	40.15
C¹/₂	0.53			12.90	40.53
	0.84	1	1³/₄	13.00	40.84
	1.00			13.05	41.00

Britain Europe Japan USA Diameter Circumference
D 1.15 13.10 41.15
1.50 2 13.21 41.50
D¹/₂ 1.78 13.30 41.78
1.88 2 13.33 41.88
2.00 13.37 42.00
2.13 2¹/₄ 13.41 42.13
E 2.41 13.50 42.41
2.76 2¹/₂ 13.61 42.76
2.91 3 13.66 42.91
E¹/₂ 3.00 13.69 43.00
3.42 2³/₄ 13.82 43.42
F 3.67 13.90 43.67
3.98 4 14.00 43.98
4.00 14.01 44.00
4.14 3 14.05 44.14

Britain Europe Japan USA Diameter Circumference
F¹/₂ 4.30 14.10 44.30
4.74 3¹/₄ 14.24 44.74
G 4.92 14.30 44.92
5.00 14.32 45.00
5.02 5 14.33 45.02
5.40 3¹/₂ 14.45 45.40
G¹/₂ 5.55 14.50 45.55
6.00 14.64 46.00
6.02 3³/₄ 14.65 46.02
6.06 6 14.66 46.06
H 6.18 14.70 46.18
6.68 4 14.86 46.68

Britain Europe Japan USA Diameter Circumference
H¹/₂ 6.81 14.90 46.81
7.00 14.96 47.00
7.12 7 15.00 47.12
7.34 4¹/₄ 15.07 47.34
I 7.44 15.10 47.44
7.97 4¹/₂ 15.27 47.97
8.00 15.28 48.00
I¹/₂ 8.07 15.30 48.07
8.16 8 15.33 48.16
8.63 4³/₄ 15.48 48.63
J 8.69 15.50 48.69
9.00 15.60 49.00
9.20 9 15.66 49.20

Britain Europe Japan USA Diameter Circumference
J¹/₂ 9.32 5 15.70 49.32
K 9.95 5¹/₄ 15.90 49.95
10.00 15.92 50.00
10.27 10 16.00 50.27
K¹/₂ 10.58 5¹/₂ 16.10 50.58
11.00 16.23 51.00
L 11.24 5³/₄ 16.31 51.24
11.30 11 16.33 51.30
L¹/₂ 11.87 6 16.51 51.87
12.00 16.55 52.00
12.34 12 16.66 52.34
M 12.46 16.70 52.46
12.56 6¹/₄ 16.73 52.56
13.00 16.87 53.00

Britain Europe Japan USA Diameter Circumference
M¹/₂ 13.09 16.90 53.09
13.16 6¹/₂ 16.92 53.16
13.41 13 17.00 53.41
N 13.72 17.10 53.72
13.85 6³/₄ 17.14 53.85
14.00 17.19 54.00
N¹/₂ 14.35 17.30 54.35
14.44 14 17.33 54.44
14.51 7 17.35 54.51
O 14.98 17.50 54.98
15.00 7¹/₄ 17.56 55.00
15.48 15 17.66 55.48

Britain Europe Japan USA Diameter Circumference
O¹/₂ 15.61 17.70 55.61
15.76 7¹/₂ 17³/₄ 55.76
16.00 17.83 56.00
P 16.23 17.90 56.23
16.45 7³/₄ 17.97 56.45
16.55 16 18.00 56.55
P¹/₂ 16.86 18.10 56.86
17.00 18.14 57.00
17.15 8 18.19 57.15
Q 17.49 18.30 57.49
17.59 17 18.33 57.59
17.77 8¹/₄ 18.39 57.77
18.00 18.46 58.00

Britain Europe Japan USA Diameter Circumference
Q¹/₂ 18.12 18.50 58.12
18.40 8¹/₂ 18.59 58.40
18.62 18 18.66 58.62
R 18³/₄ 18.70 58³/₄
19.00 8³/₄ 18.78 59.00
R¹/₂ 19.38 18.90 59.38
19.66 9 18.99 59.66
19.69 19 19.00 59.69
S 20.00 19.10 60.00
20.38 9¹/₄ 19.22 60.38
S¹/₂ 20.63 19.30 60.63
20.73 20 19.33 60.73
20.98 9¹/₂ 19.41 60.98
21.00 19.42 61.00

Britain Europe Japan USA Diameter Circumference
T 21.26 19.50 61.26
21.67 9³/₄ 19.63 61.67
21.76 21 19.66 61.76
T¹/₂ 21.89 19.70 61.89
22.00 19.74 62.00
22.33 10 19.84 62.33
U 22.52 19.90 62.52
22.83 22 20.00 62.83
23.00 10¹/₄ 20.05 63.00
U¹/₂ 23.15 20.10 63.15
23.59 10¹/₂ 20.24 63.59

Britain Europe Japan USA Diameter Circumference
V 23.77 20.30 63.77
23.87 23 20.33 63.87
23.99 20.37 63.99
24.28 10³/₄ 20.46 64.28
V¹/₂ 24.40 20.50 64.40
24.91 24 20.66 64.91
24.97 11 20.68 64.97
W 25.00 20.69 65.00
25.60 11¹/₄ 20.88 65.60

Britain Europe Japan USA Diameter Circumference
W¹/₂ 25.66 20.90 65.66
25.97 25 21.00 65.97
26.00 21.01 66.00
26.22 11¹/₂ 21.08 66.22
X 26.29 21.10 66.29
X¹/₂ 26.92 10³/₄ 21.30 66.92
27.01 26 21.33 67.01
Y 27.51 12 21.49 67.51
28.02 21.65 68.02
28.05 27 21.66 68.05
Y¹/₂ 28.20 12¹/₄ 21.71 68.20
Z 28.77 12¹/₂ 21.89 68.77
28.99 21.96 68.99
29.12 28 22.00 69.12

Britain Europe Japan USA Diameter Circumference
Z¹/₂ 29.43 22.10 69.43
29.49 12³/₄ 22.12 69.49
Z+1 29.99 22.28 69.99
30.15 29 13 22.33 70.15
Z+1¹/₂ 30.69 22.50 70.69
30.81 13¹/₄ 22.54 70.81
31.00 22.60 71.00
31.19 30 22.66 71.19
Z+2 31.31 22.70 71.31
31.47 13¹/₂ 22³/₄ 71.47
Z+2¹/₂ 32.01 13³/₄ 22.92 72.01
32.26 31 23.00 72.26

Britain Europe Japan USA Diameter Circumference
Z+3 32.57 23.10 72.57
32.76 14 23.16 72.76
33.01 23.24 73.01
Z+3¹/₂ 33.20 23.30 73.20
33.32 23.34 73.32
33.29 32 23.33 73.29
33.42 14¹/₄ 23.37 73.42
Z+4 33.83 23.50 73.83
33.98 14¹/₂ 23.55 73.98
34.33 33 23.66 74.33
Z+4¹/₂ 34.46 23.70 74.46
34.71 14³/₄ 23.78 74.71
34.99 23.87 74.99

Britain Europe Japan USA Diameter Circumference
Z+5 35.08 23.90 75.08
35.40 34 15 24.00 75.40
Z+5¹/₂ 35.71 24.10 75.71
36.00 15¹/₄ 24.19 76.00
Z+6 36.34 24.30 76.34
36.43 35 24.33 76.43
36.69 15¹/₂ 24.41 76.69
Z+6¹/₂ 37.00 24.51 77.00
37.31 15³/₄ 24.61 77.31
37.47 36 24.66 77.47
Z+7 37.60 24.70 77.60
38.00 16 24.83 78.00
Z+7¹/₂ 38.23 24.90 78.23
38.54 37 16¹/₄ 25.00 78.54

© Lawrence Chard 1999
Other jewellers are welcome to use this chart.
You may ask to copy this chart provided you agree to attach an acknowledgment and copyright notice to your copy.

Formula:-
Diameter = (British Size x .4) + 11.5; where A = 1, B = 2, Z = 26, etc.
Diameter = (American Size x 0.83) + 11.5
European Size = Circumference - 40
Diameter = (Japanese Size / 3) +12.67
In all cases, diameter is in millimetres.

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J. Thomson Custom Jewelers
(A wholly owned subsidiary of Opals International Jewelers, Inc.)
5770 NW Expressway, Suite 101
Oklahoma City, OK 73132
1-800-376-6725
(405) 495-6610
FAX (405) 728-1914
Email: gems@customfinejewelry.com