Ring Size Comparison Chart compliments of the International Gem Society. A conversion table of Ring sizes. 7 different ring size equivalents available.
| US Standard (Also Canada) | Diameter in Inches | British Equivalent | French Equivalent | German Equivalent | Swiss Equivalent | Japanese Equivalent |
| 0 | .454 | - | - | - | - | - |
| 1/2 | - | A | - | - | - | - |
| 1 | .487 | B | - | - | - | 1 |
| 1 1/2 | .503 | C | - | - | - | - |
| 2 | .520 | D | 41 ½ | 13 ¼ | 1 ½ | 2 |
| 2 1/2 | .536 | E | 42 ¾ | 13 ¾ | 2 ¾ | 3 |
| 3 | .553 | F | 44 | 14 | 4 | 4 |
| 3 3/8 | - | G | 45 ½ | - | 5 ½ | 5 |
| 3 1/2 | .569 | - | - | 14 ½ | - | - |
| 3 3/4 | - | H | 46 ½ | - | 6 ½ | - |
| 4 | .585 | H ½ | - | 15 | - | 7 |
| 4 1/4 | - | I | 47 ¾ | - | 7 ¾ | - |
| 4 7/8 | - | J | 49 | - | 9 | - |
| 5 | .618 | J ½ | - | 15 ¾ | - | 9 |
| 5 1/8 | - | K | 50 | - | 10 | - |
| 5 1/2 | .634 | L | 51 ¾ | 16 | 11 ¾ | - |
| 6 | .650 | M | 52 ¾ | 16 ½ | 12 ¾ | 12 |
| 6 1/2 | .666 | N | 54 | 17 | 14 | 13 |
| 7 | .683 | O | 55 ¼ | 17 ¼ | 15 ¼ | 14 |
| 7 1/4 | .699 | P | 56 ½ | 17 ¾ | 16 ½ | 15 |
| 8 | .716 | Q | 57 ¾ | 18 | 17 ¾ | 16 |
| 8 1/2 | .732 | - | - | 18 ½ | - | 17 |
| 8 5/8 | - | R | 59 | - | 19 | - |
| 9 | .748 | - | - | 19 | - | 18 |
| 9 1/8 | - | S | 60 ¼ | - | 20 ¼ | - |
| 9 1/4 | .764 | - | - | 19 ½ | - | 19 |
| 9 5/8 | - | T | 61 ½ | - | 21 ½ | - |
| 10 | .781 | T ½ | - | 20 | - | 20 |
| 10 1/4 | - | U | 62 ¾ | - | 22 ¾ | 21 |
| 10 1/2 | .797 | U ½ | - | 20 ¼ | - | 22 |
| 10 5/8 | - | V | 63 ¾ | - | 23 ¾ | - |
| 11 | .814 | V ½ | - | 20 ¾ | - | 23 |
| 11 1/8 | - | W | 65 | - | 25 | - |
| 11 1/2 | .830 | - | - | 21 | - | 24 |
| 11 5/8 | - | X | 66 ¼ | - | 26 ¼ | - |
| 12 | .846 | Y | 67 ½ | 21 ¼ | 27 ½ | 25 |
| 12 1/2 | .862 | Z | 68 ¾ | 21 ¾ | 28 ¾ | 26 |
| 13 | .879 | - | - | 22 | - | 27 |
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| US Standard (Also Canada) | Diameter in Inches | British Equivalent | French Equivalent | German Equivalent | Swiss Equivalent | Japanese Equivalent |
| 0 | .454 | - | - | - | - | - |
| 1/2 | - | A | - | - | - | - |
| 1 | .487 | B | - | - | - | 1 |
| 1 1/2 | .503 | C | - | - | - | - |
| 2 | .520 | D | 41 ½ | 13 ¼ | 1 ½ | 2 |
| 2 1/2 | .536 | E | 42 ¾ | 13 ¾ | 2 ¾ | 3 |
| 3 | .553 | F | 44 | 14 | 4 | 4 |
| 3 3/8 | - | G | 45 ½ | - | 5 ½ | 5 |
| 3 1/2 | .569 | - | - | 14 ½ | - | - |
| 3 3/4 | - | H | 46 ½ | - | 6 ½ | - |
| 4 | .585 | H ½ | - | 15 | - | 7 |
| 4 1/4 | - | I | 47 ¾ | - | 7 ¾ | - |
| 4 7/8 | - |
| J |
| 49 |
| - |
| 9 |
| - |
| 5 | .618 | J ½ | - | 15 ¾ | - | 9 |
| 5 1/8 | - | K | 50 | - | 10 | - |
| 5 1/2 | .634 | L | 51 ¾ | 16 | 11 ¾ | - |
| 6 | .650 | M | 52 ¾ | 16 ½ | 12 ¾ | 12 |
| 6 1/2 | .666 | N | 54 | 17 | 14 | 13 |
| 7 | .683 | O | 55 ¼ | 17 ¼ | 15 ¼ | 14 |
| 7 1/4 | .699 | P | 56 ½ | 17 ¾ | 16 ½ | 15 |
| 8 | .716 | Q | 57 ¾ | 18 | 17 ¾ | 16 |
| 8 1/2 | .732 | - | - | 18 ½ | - | 17 |
| 8 5/8 | - | R | 59 | - | 19 | - |
| 9 | .748 | - | - | 19 | - | 18 |
| 9 1/8 | - | S | 60 ¼ | - | 20 ¼ | - |
| 9 1/4 | .764 | - | - | 19 ½ | - | 19 |
| 9 5/8 | - | T | 61 ½ | - | 21 ½ | - |
| 10 | .781 | T ½ | - | 20 | - | 20 |
| 10 1/4 | - | U | 62 ¾ | - | 22 ¾ | 21 |
| 10 1/2 | .797 | U ½ | - | 20 ¼ | - | 22 |
| 10 5/8 | - | V | 63 ¾ | - | 23 ¾ | - |
| 11 | .814 | V ½ | - | 20 ¾ | - | 23 |
| 11 1/8 | - | W | 65 | - | 25 | - |
| 11 1/2 | .830 | - | - | 21 | - | 24 |
| 11 5/8 | - | X | 66 ¼ | - | 26 ¼ | - |
| 12 | .846 | Y | 67 ½ | 21 ¼ | 27 ½ | 25 |
| 12 1/2 | .862 | Z | 68 ¾ | 21 ¾ | 28 ¾ | 26 |
| 13 | .879 | - | - | 22 | - | 27 |
Compliments of The International Gem Society