Ring Size Comparison Chart
We have compiled an approximate comparison chart of various ring size measurement systems used across the globe. This guide is there to help you choose correct ring size no matter where you are in the world.
Make sure you check your size using as many tools as possible, as some variation is always present.
| Inside Diameter | Inside Circumference | Size Comparison | |||||||
| MM | Inches | MM | Inches | British And Australian | US And Canada | French And Russian | German | Japanese | Swiss |
| 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 | - | - | - | - | - |