Guide
Ring Size Guide
Find your perfect fit.
Finding Your Size
The most accurate way to determine your ring size is to visit a local jeweler for professional sizing. If that's not possible, you can measure at home using one of the methods below.
Keep in mind that ring size can vary slightly throughout the day and with temperature changes. For the most accurate measurement, size your finger at the end of the day when it's at its largest, and when your hands are at a normal temperature.
Method 1: Measure an Existing Ring
If you have a ring that fits the finger you're sizing for, this is the easiest method.
- Select a ring that fits comfortably on the intended finger
- Measure the inside diameter of the ring in millimeters
- Use the size chart below to find your corresponding size
Make sure to measure the inside diameter (the widest point across the interior of the ring), not the outside.
Method 2: Measure Your Finger
If you don't have an existing ring to measure, you can measure your finger directly.
- Cut a thin strip of paper or use a flexible measuring tape
- Wrap it around the base of your finger, just below the knuckle
- Mark where the paper overlaps to complete the circle
- Measure the length in millimeters — this is your circumference
- Use the size chart below to find your corresponding size
The paper should be snug but not tight. You should be able to slide it over your knuckle comfortably.
Sizing Tips
When in doubt, size up. It's easier to resize a ring down than up, and a slightly loose ring is more comfortable than one that's too tight. If you're between sizes, choose the larger size. For wider bands (over 6mm), consider going up a half size, as wider rings fit more snugly.
| US Size | Inside Diameter (mm) | Circumference (mm) | UK/AU Size | EU Size |
|---|---|---|---|---|
| 4 | 14.9 | 46.8 | H | 47 |
| 4.5 | 15.3 | 48.0 | I | 48 |
| 5 | 15.7 | 49.3 | J ½ | 49 |
| 5.5 | 16.1 | 50.6 | K ½ | 51 |
| 6 | 16.5 | 51.8 | L ½ | 52 |
| 6.5 | 16.9 | 53.1 | M ½ | 53 |
| 7 | 17.3 | 54.4 | N ½ | 54 |
| 7.5 | 17.7 | 55.6 | O ½ | 56 |
| 8 | 18.1 | 56.9 | P ½ | 57 |
| 8.5 | 18.5 | 58.1 | Q ½ | 58 |
| 9 | 18.9 | 59.4 | R ½ | 59 |
| 9.5 | 19.4 | 60.9 | S ½ | 61 |
| 10 | 19.8 | 62.2 | T ½ | 62 |
Resizing
Most SEMRA rings can be resized within 1–2 sizes up or down. We offer one complimentary resize within 30 days of purchase.
Some designs have limitations due to intricate details, channel-set stones, or eternity bands. If you have questions about resizing a specific design, please contact us before ordering.
Still Unsure?
If you're uncertain about your size, especially for an engagement ring or special piece, we recommend:
- Visiting a local jeweler for professional sizing
- Contacting us — we can discuss your options and help you choose
- For bespoke pieces, sizing is confirmed during the design process
