Ring Size Guide
MethodÂ
Measure a ring you already love.
- Choose a ring that fits the finger you plan to wear your new piece on.
- Lay it flat on a ruler and measure straight across the inside, edge to edge, in millimetres.
- Find that number in our size chart.
How to measure the inside diameter of a ring.

Good to know.
- Measure twice. A millimetre either way can change your size.
- Measure late in the day. Fingers are fullest in the afternoon when your hands are warm, and a little smaller in the morning or the cold. If you land between sizes, go up.
- Measure the exact finger. Every finger is different, and so is each hand.
Can my ring be resized?
Fingers change over the years, and your ring can change with them. We don't offer resizing, but if your ring has a plain section of band, most local jewellers can adjust it when the time comes.Â
Eternity bands are the exception. With diamonds all the way round, there's nowhere to adjust, so the size you choose is the size it stays. That's the trade for sparkle from every angle.
Even on rings that can be adjusted, big changes of more than two sizes can alter how a ring sits and looks.
Ring Size Conversion Chart
| Sizes | Inside diameter | Inside circumference | |||
|---|---|---|---|---|---|
| Australia, NZ, UK & Ireland | United States & Canada | (mm) | (in) | (mm) | (in) |
| A | ½ | 12.04 | 0.474 | 37.8 | 1.49 |
| A½ | ¾ | 12.24 | 0.482 | 38.5 | 1.51 |
| B | 1 | 12.45 | 0.490 | 39.1 | 1.54 |
| B½ | 1¼ | 12.65 | 0.498 | 39.7 | 1.56 |
| C | 1½ | 12.85 | 0.506 | 40.4 | 1.59 |
| C½ | 1¾ | 13.06 | 0.514 | 41.0 | 1.61 |
| D | 2 | 13.26 | 0.522 | 41.7 | 1.64 |
| D½ | 2¼ | 13.46 | 0.530 | 42.3 | 1.67 |
| E | 2½ | 13.67 | 0.538 | 42.9 | 1.69 |
| E½ | 2¾ | 13.87 | 0.546 | 43.6 | 1.72 |
| F | 3 | 14.07 | 0.554 | 44.2 | 1.74 |
| F½ | 3¼ | 14.27 | 0.562 | 44.8 | 1.77 |
| G | 3½ | 14.48 | 0.570 | 45.5 | 1.79 |
| G½ | 3¾ | 14.68 | 0.578 | 46.1 | 1.82 |
| H | 4 | 14.88 | 0.586 | 46.8 | 1.84 |
| H½ | 4¼ | 15.09 | 0.594 | 47.4 | 1.87 |
| I | 4½ | 15.29 | 0.602 | 48.0 | 1.89 |
| J | 4¾ | 15.49 | 0.610 | 48.7 | 1.92 |
| J½ | 5 | 15.70 | 0.618 | 49.3 | 1.94 |
| K | 5¼ | 15.90 | 0.626 | 50.0 | 1.97 |
| K½ | 5½ | 16.10 | 0.634 | 50.6 | 1.99 |
| L | 5¾ | 16.31 | 0.642 | 51.2 | 2.02 |
| L½ | 6 | 16.51 | 0.650 | 51.9 | 2.04 |
| M | 6¼ | 16.71 | 0.658 | 52.5 | 2.07 |
| M½ | 6½ | 16.92 | 0.666 | 53.1 | 2.09 |
| N | 6¾ | 17.12 | 0.674 | 53.8 | 2.12 |
| N½ | 7 | 17.32 | 0.682 | 54.4 | 2.14 |
| O | 7¼ | 17.53 | 0.690 | 55.1 | 2.17 |
| O½ | 7½ | 17.73 | 0.698 | 55.7 | 2.19 |
| P | 7¾ | 17.93 | 0.706 | 56.3 | 2.22 |
| P½ | 8 | 18.14 | 0.714 | 57.0 | 2.24 |
| Q | 8¼ | 18.34 | 0.722 | 57.6 | 2.27 |
| Q½ | 8½ | 18.54 | 0.730 | 58.3 | 2.29 |
| R | 8¾ | 18.75 | 0.738 | 58.9 | 2.32 |
| R½ | 9 | 18.95 | 0.746 | 59.5 | 2.34 |
| S | 9¼ | 19.15 | 0.754 | 60.2 | 2.37 |
| S½ | 9½ | 19.35 | 0.762 | 60.8 | 2.39 |
| T | 9¾ | 19.56 | 0.770 | 61.4 | 2.42 |
| T½ | 10 | 19.76 | 0.778 | 62.1 | 2.44 |
| U | 10¼ | 19.96 | 0.786 | 62.7 | 2.47 |
| U½ | 10½ | 20.17 | 0.794 | 63.4 | 2.49 |
| V | 10¾ | 20.37 | 0.802 | 64.0 | 2.52 |
| V½ | 11 | 20.57 | 0.810 | 64.6 | 2.54 |
| W | 11¼ | 20.78 | 0.818 | 65.3 | 2.57 |
| W½ | 11½ | 20.98 | 0.826 | 65.9 | 2.59 |
| X | 11¾ | 21.18 | 0.834 | 66.6 | 2.62 |
| X½ | 12 | 21.39 | 0.842 | 67.2 | 2.65 |
| Y | 12¼ | 21.59 | 0.850 | 67.8 | 2.67 |
| Z | 12½ | 21.79 | 0.858 | 68.5 | 2.70 |
| Z½ | 12¾ | 22.00 | 0.866 | 69.1 | 2.72 |

