US:
N/A
D: N/A
C: N/A
UK:
N/A
D: N/A
C: N/A
Europe:
N/A
D: N/A
C: N/A
Switzerland:
N/A
D: N/A
C: N/A
Japan:
N/A
D: N/A
C: N/A
Brazil:
N/A
D: N/A
C: N/A

D = diameter, C = circumference

Ring sizes can be tricky, even more so if you are buying one from an international seller or buying one when you are on your travels, which is why we created an easy-to-use tool that lets you quickly and easily see what that size is equivalent to in other popular ring size standards.

To use the ring size conversion tool, simply:

US Ring Size Conversion Chart

Below we have also included a full US ring size conversion chart that shows:

US ring sizes are also used in Canada and Mexico.

USA/Canada UK/Australia Europe Switzerland Japan Brazil Diameter
(mm/in)		 Circumference
(mm/in)
0.5 A 11.9 mm / 0.47 in 37.4 mm / 1.47 in
1 A 1/2 12.3 mm / 0.48 in 38.6 mm / 1.52 in
1.25 B 12.6 mm / 0.50 in 39.6 mm / 1.56 in
1.5 12.8 mm / 0.50 in 40.1 mm / 1.58 in
1.75 C 1 13.0 mm / 0.51 in 40.8 mm / 1.61 in
2 C 1/2 13.2 mm / 0.52 in 41.5 mm / 1.63 in
2.25 D 2 13.4 mm / 0.53 in 42.1 mm / 1.66 in
2.5 D 1/2 13.6 mm / 0.54 in 42.8 mm / 1.69 in
2.75 E 1/2 3 13.8 mm / 0.54 in 43.4 mm / 1.71 in
3 E 1/2 44 4 4 7 14.0 mm / 0.55 in 44.0 mm / 1.73 in
3.25 F 14.2 mm / 0.56 in 44.7 mm / 1.76 in
3.5 F 1/2 45 4.5 5 8 14.4 mm / 0.57 in 45.4 mm / 1.79 in
3.75 G 1/2 46 5 6 9 14.7 mm / 0.58 in 46.2 mm / 1.82 in
4 H 14.9 mm / 0.59 in 46.8 mm / 1.84 in
4.25 H 1/2 47 5.5 7 10 15.1 mm / 0.59 in 47.4 mm / 1.87 in
4.5 I 48 6 8 11 15.3 mm / 0.60 in 48.1 mm / 1.89 in
4.75 J 15.5 mm / 0.61 in 48.7 mm / 1.92 in
5 J 1/2 49 6.5 9 12 15.7 mm / 0.62 in 49.3 mm / 1.94 in
5.25 K 50 7 10 13 15.9 mm / 0.63 in 50.0 mm / 1.97 in
5.5 K 1/2 16.1 mm / 0.63 in 50.6 mm / 1.99 in
5.75 L 51 7.5 11 14 16.3 mm / 0.64 in 51.2 mm / 2.02 in
6 L 1/2 52 15 16.5 mm / 0.65 in 51.9 mm / 2.04 in
6.25 M 8 12 16.7 mm / 0.66 in 52.5 mm / 2.07 in
6.5 M 1/2 53 8.5 16 16.9 mm / 0.67 in 53.1 mm / 2.09 in
6.75 N 13 17.1 mm / 0.67 in 53.8 mm / 2.12 in
7 N 1/2 54 9 14 17 17.3 mm / 0.68 in 54.5 mm / 2.15 in
7.25 O 55 9.5 18 17.5 mm / 0.69 in 55.0 mm / 2.17 in
7.5 O 1/2 15 17.7 mm / 0.70 in 55.8 mm / 2.20 in
7.75 P 56 10 19 17.9 mm / 0.70 in 56.4 mm / 2.22 in
8 P 1/2 57 10.5 16 20 18.1 mm / 0.71 in 57.0 mm / 2.24 in
8.25 Q 17 18.3 mm / 0.72 in 57.6 mm / 2.27 in
8.5 Q 1/2 58 11 21 18.5 mm / 0.73 in 58.2 mm / 2.29 in
8.75 R 59 11.5 18 22 18.8 mm / 0.74 in 59.1 mm / 2.33 in
9 R 1/2 19 19.0 mm / 0.75 in 59.7 mm / 2.35 in
9.25 S 60 12 19.2 mm / 0.76 in 60.3 mm / 2.37 in
9.5 S 1/2 61 12.5 20 24 19.4 mm / 0.76 in 61.0 mm / 2.40 in
9.75 T 19.6 mm / 0.77 in 61.6 mm / 2.43 in
10 T 1/2 62 13 21 25 19.8 mm / 0.78 in 62.2 mm / 2.45 in
10.25 U 20.0 mm / 0.79 in 62.8 mm / 2.47 in
10.5 U 1/2 63 13.5 22 26 20.2 mm / 0.80 in 63.5 mm / 2.50 in
10.75 V 64 14 23 27 20.5 mm / 0.81 in 64.4 mm / 2.54 in
11 V 1/2 65 14.5 24 28 20.7 mm / 0.81 in 65.0 mm / 2.56 in
11.25 W 20.9 mm / 0.82 in 65.6 mm / 2.58 in
11.5 X 66 15 25 29 21.1 mm / 0.83 in 66.2 mm / 2.61 in
11.75 X 1/2 67 15.5 30 21.3 mm / 0.84 in 66.9 mm / 2.63 in
12 Y 21.5 mm / 0.85 in 67.5 mm / 2.66 in
12.25 Y 1/2 68 16 27 31 21.7 mm / 0.85 in 68.1 mm / 2.68 in
12.5 Z 69 21.9 mm / 0.86 in 68.8 mm / 2.71 in
12.75 Z 1/2 69 16.5 28 32 22.1 mm / 0.87 in 69.4 mm / 2.73 in
13 70 17 29 33 22.3 mm / 0.88 in 70.0 mm / 2.76 in