International Ring Size Conversion Chart

The information presented here has been compiled from many sources in various countries to help you determine your local ring size compared to those from other countries.
The standards included in this resource are from the US & Canada, United Kingdom & Australia, France & Russia, Germany, Japan and Switzerland.

Inside Diameter  Inside Circumference Sizes MM Inches MM Inches British & Australian  US & Canada French & Russian German Japanese Swiss 9.91 0.390 31.13 1.22 - 0000 - - - - 10.72 0.442 33.68 1.39 - 00 - - - - 11.53 0.454 36.22 1.43 - 0 - - - - 11.95 0.474 37.54 1.49 A 1/2 - - - - 12.18 0.482 38.26 1.51 A 1/2 3/4 - - - - 12.37 0.487 38.86 1.53 B 1 - - 1 - 12.60 0.496 39.58 1.56 B 1/2 1 1/4 - - - - 12.78 0.503 40.15 1.58 C 1 1/2 - - - - 13.00 0.512 40.84 1.61 C 1/2 1 3/4 - - - - 13.21 0.520 41.50 1.63 D 2 41 1/2 13 1/2 2 1 1/2 13.41 0.528 42.13 1.66 D 1/2 2 1/4 - - - - 13.61 0.536 42.76 1.68 E 2 1/2 42 3/4 13 3/4 3 2 3/4 13.83 0.544 43.45 1.71 E 1/2 2 3/4 - - - - 14.05 0.553 44.14 1.74 F 3 44 14 4 4 14.15 0.557 44.45 1.75 F 1/2 3 1/8 - - - - 14.25 0.561 44.77 1.76 F 3/4 3 1/4 - - - - 14.36 0.565 45.11 1.77 G 3 3/8 45 1/4 - 5 5 1/4 14.45 0.569 45.40 1.79 G 1/4 3 1/2 - 14 1/2 - - 14.56 0.573 45.74 1.80 G 1/2 3 5/8 - - 6 - 14.65 0.577 46.02 1.81 H 3 3/4 46 1/2 - - 6 1/2 14.86 0.585 46.68 1.84 H 1/2 4 - 15 7 - 15.04 0.592 47.25 1.86 I 4 1/4 47 3/4 - - 7 3/4 15.27 0.601 47.97 1.89 I 1/2 4 1/2 - 15 1/4 8 - 15.40 0.606 48.38 1.90 J 4 5/8 49 15 1/2 - 9 15.53 0.611 48.79 1.92 J 1/4 4 3/4 - - - - 15.70 0.618 49.32 1.94 J 1/2 5 - 15 3/4 9 - 15.80 0.622 49.64 1.95 K 5 1/8 50 - - 10 15.90 0.626 49.95 1.97 K 1/4 5 1/4 - - - - 16.00 0.630 50.27 1.98 K 1/2 5 3/8 - - 10 - 16.10 0.634 50.58 1.99 L 5 1/2 51 3/4 16 - 11 3/4 16.30 0.642 51.21 2.02 L 1/4 5 3/4 - - - - 16.41 0.646 51.55 2.03 L 1/2 5 7/8 - - - - 16.51 0.650 51.87 2.04 M 6 52 3/4 16 1/2 12 12 3/4 16.71 0.658 52.50 2.07 M 1/2 6 1/4 - - - - 16.92 0.666 53.16 2.09 N 6 1/2 54 17 13 14 17.13 0.674 53.82 2.12 N 1/2 6 3/4 - - - - 17.35 0.683 54.51 2.15 O 7 55 1/4 17 1/4 14 15 1/4 17.45 0.687 54.82 2.16 O 1/2 7 1/4 - - - - 17.75 0.699 55.76 2.20 P 7 1/2 56 1/2 17 3/4 15 16 1/2 17.97 0.707 56.45 2.22 P 1/2 7 3/4 - - - - 18.19 0.716 57.15 2.25 Q 8 57 3/4 18 16 17 3/4 18.35 0.722 57.65 2.27 Q 1/2 8 1/4 - - - - 18.53 0.729 58.21 2.29 Q 3/4 8 1/2 - 18 1/2 17 - 18.61 0.733 58.47 2.30 R 8 5/8 59 - - 19 18.69 0.736 58.72 2.31 R 1/4 8 3/4 - - - - 18.80 0.740 59.06 2.32 R 1/2 8 7/8 - - - - 18.89 0.748 59.34 2.35 R 3/4 9 - 19 18 - 19.10 0.752 60.00 2.36 S 9 1/8 60 1/4 - - 20 1/4 19.22 0.757 60.38 2.38 S 1/4 9 1/4 - - - - 19.31 0.760 60.66 2.39 S 1/2 9 3/8 - - - - 19.41 0.764 60.98 2.40 S 3/4 9 1/2 - 19 1/2 19 - 19.51 0.768 61.29 2.41 T 9 5/8 61 1/2 - - 21 1/2 19.62 0.772 61.64 2.43 T 1/4 9 3/4 - - - - 19.84 0.781 62.33 2.45 T 1/2 10 - 20 20 - 20.02 0.788 62.89 2.48 U 10 1/4 62 3/4 - 21 22 3/4 20.20 0.797 63.46 2.50 U 1/2 10 1/2 - 20 1/4 22 - 20.32 0.800 63.84 2.51 V 10 5/8 63 - - 23 3/4 20.44 0.805 64.21 2.53 V 1/4 10 3/4 - - - - 20.68 0.814 64.97 2.56 V 1/2 11 - 20 3/4 23 - 20.76 0.817 65.22 2.57 W 11 1/8 65 - - 25 20.85 0.821 65.50 2.58 W 1/4 11 1/4 - - - - 20.94 0.824 65.78 2.59 W 1/2 11 3/8 - - - - 21.08 0.830 66.22 2.61 W 3/4 11 1/2 - 21 24 - 21.18 0.834 66.54 2.62 X 11 5/8 66 1/4 - - 26 1/4 21.24 0.836 66.73 2.63 X 1/4 11 3/4 - - - - 21.30 0.839 66.92 2.64 X 1/2 11 7/8 - - - - 21.49 0.846 67.51 2.66 Y 12 67 1/2 21 1/4 25 27 1/2 21.69 0.854 68.14 2.68 Y 1/2 12 1/4 - - - - 21.89 0.862 68.77 2.71 Z 12 1/2 68 3/4 21 3/4 26 28 3/4 22.10 0.870 69.43 2.73 Z +1/2 12 3/4 - - - - 22.33 0.879 70.15 2.76 Z+1 13 - 22 27 - 22.60 0.890 71.00 2.80 Z+1.5 13.5 - - - - 22.69 0.893 71.28 2.81 Z+2 - - - - - 22.92 0.902 72.00 2.83 Z+2.5 - - - - - 23.06 0.908 72.45 2.85 Z+3 - - - - - 23.24 0.915 73.01 2.87 Z+3.5 - - - - - 23.47 0.924 73.73 2.90 Z+4 - - - - - 23.55 0.927 73.98 2.91 Z+4.5 - - - - - 23.87 0.940 74.99 2.95 Z+5 - - - - - 24.27 0.956 76.25 3.00 Z+6 - - - - -