Short answer: measure the inside diameter of a ring that already fits that finger, or wrap a strip of paper around the finger and measure its length, then read it off a conversion chart. Measure at the end of the day at normal room temperature, when fingers are at their largest. Aetheris makes US sizes 5 to 10, including half sizes.
Every Aetheris ring is made to order in the size you choose, so getting the size right before you order matters. This guide shows two simple ways to measure at home and a US size chart for the sizes we make.
Method 1: measure a ring that already fits
- Choose a ring that fits the finger you plan to wear the new ring on.
- Place it on a flat surface and measure the inside diameter in millimetres, from inner edge to inner edge across the widest point.
- Find the nearest diameter in the chart below.
This is the most reliable home method, as long as the ring you measure is not bent and fits comfortably.
Method 2: measure your finger with a strip of paper
- Cut a thin strip of paper, or use a piece of non-stretch string.
- Wrap it around the base of your finger so it sits snugly but can still slide over the knuckle.
- Mark where the end overlaps, then lay it flat and measure the length in millimetres. This is your finger's circumference.
- Find the nearest circumference in the chart below.
US ring size chart
| US size | Inside diameter (mm) | Circumference (mm) |
|---|---|---|
| 5 | 15.7 | 49.3 |
| 5.5 | 16.1 | 50.6 |
| 6 | 16.5 | 51.9 |
| 6.5 | 16.9 | 53.1 |
| 7 | 17.3 | 54.4 |
| 7.5 | 17.7 | 55.7 |
| 8 | 18.1 | 57.0 |
| 8.5 | 18.6 | 58.3 |
| 9 | 18.9 | 59.5 |
| 9.5 | 19.4 | 60.8 |
| 10 | 19.8 | 62.1 |
Our rings are offered in US sizes 5 to 10, including half sizes. Know your size from another country? Use our international ring size chart to convert it.
Tips for an accurate measurement
- Measure at the end of the day. Fingers are often slightly larger in the evening and in warm weather, and smaller when cold.
- Check the knuckle. The ring has to pass over it. If your knuckle is much wider than the base of your finger, choose the size that slides over the knuckle.
- Measure two or three times. If your results fall between two sizes, the larger size is usually more comfortable.
- Consider the band width. Wider bands tend to feel tighter than thin bands in the same size.
- Buying a surprise gift? Borrow a ring the person already wears on the same finger and use Method 1.
Why sizing matters with made-to-order jewelry
Each ring is produced for you in 10 working days in the size, metal and stone you select. Because it is made specifically for your order, we do not accept returns or offer refunds for change of mind, so please check your ring size carefully before ordering. If you are unsure, email aetheristechhk@gmail.com before you order and we will help you choose.
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