Ring Size Guide
Every Aetheris ring is made to order in US sizes 5 to 10, including half sizes. If you know your size from another country, use the chart below to find the matching US size. If you don't know your size yet, our guide How to Find Your Ring Size at Home shows two simple ways to measure.
International ring size chart
Ring sizes are matched by the inside circumference of the ring. Each country rounds its scale a little differently, so treat sizes in the same row as close equivalents and always compare the millimetres.
| US / Canada | UK / Australia | Europe | Japan / China | Diameter mm | Circumference mm | Aetheris |
|---|---|---|---|---|---|---|
| 3 | F½ | 44 | 4 | 14.1 | 44.2 | — |
| 3.5 | G½ | 45.5 | 5 | 14.5 | 45.5 | — |
| 4 | H½ | 47 | 7 | 14.9 | 46.8 | — |
| 4.5 | I½ | 48 | 8 | 15.3 | 48.0 | — |
| 5 | J½ | 49.5 | 9 | 15.7 | 49.3 | Yes |
| 5.5 | K½ | 50.5 | 11 | 16.1 | 50.6 | Yes |
| 6 | L½ | 52 | 12 | 16.5 | 51.9 | Yes |
| 6.5 | M½ | 53 | 13 | 16.9 | 53.1 | Yes |
| 7 | N½ | 54.5 | 14 | 17.3 | 54.4 | Yes |
| 7.5 | O½ | 55.5 | 16 | 17.7 | 55.7 | Yes |
| 8 | P½ | 57 | 17 | 18.1 | 57.0 | Yes |
| 8.5 | Q½ | 58.5 | 18 | 18.5 | 58.3 | Yes |
| 9 | R½ | 59.5 | 20 | 18.9 | 59.5 | Yes |
| 9.5 | S½ | 61 | 21 | 19.4 | 60.8 | Yes |
| 10 | T½ | 62 | 22 | 19.8 | 62.1 | Yes |
| 10.5 | U½ | 63.5 | 23 | 20.2 | 63.4 | — |
| 11 | V½ | 64.5 | 25 | 20.6 | 64.6 | — |
| 11.5 | W½ | 66 | 26 | 21.0 | 65.9 | — |
| 12 | Y | 67 | 27 | 21.4 | 67.2 | — |
| 12.5 | Z | 68.5 | 28 | 21.8 | 68.5 | — |
| 13 | Z+1 | 69.5 | 30 | 22.2 | 69.7 | — |
UK sizes also apply in Ireland and New Zealand. The Japan / China scale is close to the sizes used in Italy, Spain and Switzerland. Europe means ISO sizes by inside circumference. The last column shows the sizes Aetheris makes.
How to read the chart
- US and Canada use numbers in quarter and half steps. Aetheris rings are made in whole and half US sizes from 5 to 10.
- UK, Ireland, Australia and New Zealand use letters, with half sizes written as ½.
- Europe (ISO) sizes follow the inside circumference in millimetres, as used in France and Germany. Some jewelers quote the inside diameter instead, so check which one you have.
- Japan, mainland China, Italy, Spain and Switzerland use a numbered scale that rises by about one size for each millimetre of circumference. Local charts can differ by a size, so compare the millimetres.
If you are between sizes
- Choose the larger size if your knuckle is wider than the base of your finger.
- Wider bands usually feel tighter than slim bands in the same size.
- Fingers are often slightly larger in warm weather and at the end of the day, so measure more than once.
Before you order
Each ring is produced for you in 10 working days in the size you select. Because every piece is made to order, we do not accept returns or offer refunds for change of mind, so please check your size carefully. If you are unsure, email aetheristechhk@gmail.com with your measurement and we will help you choose.
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