Ring Size Guide
Getting the size right is the difference between a ring that gets worn every day and one that sits in a drawer. This takes about two minutes.
Method 1 — Measure a ring you already own
The most accurate method, and the only one that works if you're buying a surprise gift.
- Take a ring that fits the correct finger comfortably.
- Measure the inside diameter in millimetres, edge to edge across the widest point.
- Match that measurement to the chart below.
Method 2 — Measure your finger
- Cut a strip of paper about 5mm wide.
- Wrap it around the base of your finger, snug but not tight. It needs to slide over your knuckle.
- Mark where the paper overlaps, then measure the length in millimetres. That is your circumference.
- Match it to the chart below.
Three things that change the answer
- Measure at the end of the day. Fingers are at their largest in the evening and in warm weather, and smallest first thing in the morning and in cold.
- Check the knuckle. If your knuckle is noticeably wider than the base of your finger, size to the knuckle — a ring that won't go on is worse than one slightly loose.
- Wide bands run tight. For a band 6mm or wider, go up half a size.
Size conversion chart
| Australia / UK | US | Inside diameter (mm) | Circumference (mm) |
|---|---|---|---|
| F | 3 | 14.1 | 44.2 |
| G | 3½ | 14.5 | 45.5 |
| H | 4 | 14.9 | 46.8 |
| I | 4½ | 15.3 | 48.0 |
| J | 5 | 15.7 | 49.3 |
| K | 5½ | 16.1 | 50.6 |
| L | 6 | 16.5 | 51.9 |
| M | 6½ | 16.9 | 53.1 |
| N | 7 | 17.3 | 54.4 |
| O | 7½ | 17.7 | 55.7 |
| P | 8 | 18.1 | 57.0 |
| Q | 8½ | 18.5 | 58.3 |
| R | 9 | 18.9 | 59.5 |
| S | 9½ | 19.4 | 60.8 |
| T | 10 | 19.8 | 62.1 |
| U | 10½ | 20.2 | 63.4 |
| V | 11 | 20.6 | 64.6 |
| W | 11½ | 21.0 | 65.9 |
| X | 12 | 21.4 | 67.2 |
Our moissanite and sterling silver rings are listed in US sizes. Our 9K and 18K gold rings are listed in Australian letter sizes. Use the chart above to convert between them.
Buying a surprise engagement ring
The average women's engagement ring size in Australia is between L and N (US 6 to 7). If you have no other information, N (US 7) is the safest single guess.
Better options, in order of accuracy:
- Borrow a ring she wears on her left ring finger and measure the inside diameter. A ring from another finger will not be the same size.
- Press one of her rings into a bar of soap and measure the impression.
- Ask her closest friend or her mother — they usually know, and they can usually be trusted.
If the size is wrong
We'd rather resize a ring than lose you a proposal. Every ring is covered by our 30-day return window from delivery, unworn and in original packaging. If you need a different size, email sales@giuliasecret.com and we'll sort out the exchange.
Solid gold rings can usually be resized by one or two sizes. Sterling silver eternity and full-pavé bands, and rings with stones set all the way around the band, generally cannot be resized — for those, getting the size right first time matters most.
Still not sure?
Email us at sales@giuliasecret.com with the piece you're looking at and what you know about her size. We answer within 1–2 business days, and we've done this enough times to make a good call from very little information.