Ring Size Guide
The right ring size is the one that slides over your knuckle with a little resistance and doesn't spin or slip off once it's on. Australia uses letter sizes (for example M, N or N½), and most rings on our site list their size in the description.
Quick answer: measure the inside diameter of a ring that already fits you, in millimetres, and find the closest number in the chart below. Each full letter size is 1.25mm larger around the inside than the one before, and each half size is about 0.6mm.
Australian ring size chart
Australian ring sizes follow the same letter scale as the UK, set out in British Standard BS 6820. Size C measures 40mm around the inside, and each letter after it adds 1.25mm. US sizes are numbers, and each whole US size adds about 2.55mm. Use the chart to convert a measurement or a US size to an Australian letter size.
| Australian size | Inside circumference (mm) | Inside diameter (mm) | US size |
|---|---|---|---|
| F | 43.8 | 13.9 | 2¾ |
| F½ | 44.4 | 14.1 | 3 |
| G | 45.0 | 14.3 | 3¼ |
| G½ | 45.6 | 14.5 | 3½ |
| H | 46.2 | 14.7 | 3¾ |
| H½ | 46.9 | 14.9 | 4 |
| I | 47.5 | 15.1 | 4¼ |
| I½ | 48.1 | 15.3 | 4½ |
| J | 48.8 | 15.5 | 4¾ |
| J½ | 49.4 | 15.7 | 5 |
| K | 50.0 | 15.9 | 5¼ |
| K½ | 50.6 | 16.1 | 5½ |
| L | 51.2 | 16.3 | 5¾ |
| L½ | 51.9 | 16.5 | 6 |
| M | 52.5 | 16.7 | 6¼ |
| M½ | 53.1 | 16.9 | 6½ |
| N | 53.8 | 17.1 | 6¾ |
| N½ | 54.4 | 17.3 | 7 |
| O | 55.0 | 17.5 | 7¼ |
| O½ | 55.6 | 17.7 | 7½ |
| P | 56.2 | 17.9 | 7¾ |
| P½ | 56.9 | 18.1 | 8 |
| Q | 57.5 | 18.3 | 8¼ |
| Q½ | 58.1 | 18.5 | 8½ |
| R | 58.8 | 18.7 | 8¾ |
| R½ | 59.4 | 18.9 | 9 |
| S | 60.0 | 19.1 | 9¼ |
| S½ | 60.6 | 19.3 | 9½ |
| T | 61.2 | 19.5 | 9¾ |
| T½ | 61.9 | 19.7 | 10 |
| U | 62.5 | 19.9 | 10¼ |
| U½ | 63.1 | 20.1 | 10½ |
| V | 63.8 | 20.3 | 10¾ |
| V½ | 64.4 | 20.5 | 11 |
| W | 65.0 | 20.7 | 11¼ |
| W½ | 65.6 | 20.9 | 11½ |
| X | 66.2 | 21.1 | 11¾ |
| X½ | 66.9 | 21.3 | 12 |
| Y | 67.5 | 21.5 | 12¼ |
| Y½ | 68.1 | 21.7 | 12½ |
| Z | 68.8 | 21.9 | 12¾ |
| Z½ | 69.4 | 22.1 | 13 |
Charts from different suppliers can differ by a fraction of a size, and a ring that fits is still the best guide. If you're between two sizes, choose the larger one.
How to find your ring size at home
- Use a ring that already fits (most reliable). Choose a ring worn on the same finger. Lay a ruler across the inside of the band and measure the widest point, edge to edge, in millimetres. Find that number in the inside diameter column.
- Measure your finger (rough guide only). Wrap a thin strip of paper snugly around the base of the finger, mark where it overlaps, and measure the length in millimetres. Find that number in the circumference column. Paper and string stretch and compress, so this often reads half a size or more out.
- Check the knuckle. If your knuckle is wider than the base of your finger, measure both and use the larger size so the ring can come off.
- Measure more than once. Measure at different times of day, ideally in the warmth of the afternoon, and use the most common result.
The most accurate way: come in
Visit the studio at Rovera Plaza, Shop 5, 23 Cotton Tree Parade, Cotton Tree, Maroochydore QLD 4558. We size fingers with proper ring gauges, which takes a couple of minutes and removes the guesswork. We're open Monday to Friday, 9:30am to 4:00pm, and Saturday by appointment.
If you can't visit
- Use a ring that already fits. Measure the inside diameter in millimetres, straight across the widest part of the inner edge. Send that number to us and we'll convert it to a letter size for you.
- Borrow one for a surprise. If you're buying an engagement ring, bring in one of their rings (worn on the correct finger) and we'll measure it for you.
- Be wary of string and paper. Wrapped string or paper stretches and compresses, and often reads half a size or more out. Treat it as a rough guide only.
Things that change the fit
- Time of day and temperature. Fingers are smaller in the cold and early morning, and larger in heat, after exercise or late in the day. On the Sunshine Coast, size in the warmth of the afternoon.
- Band width. A wide band sits tighter than a fine one in the same size. For bands wider than about 6mm, it's often worth going up half a size.
- Knuckles. If your knuckle is larger than the base of your finger, size for the knuckle so the ring can come off, and ask us about options for keeping it from spinning.
- Which hand. Your dominant hand is usually slightly larger.
Converting US ring sizes to Australian sizes
A US size 7 is an Australian N½, a US 6 is an L½, and a US 8 is a P½. Rings bought overseas or online are often sized in numbers, so check the US column of the chart before you order.
Resizing
Resizing is complimentary on rings bought from us, where the design allows. Some designs can't be resized, such as full eternity bands with stones all the way around and some coil or tension styles, so check the product description or ask us. If you're unsure of the size, talk to us before you buy.
Questions? Call 07 5443 1955, email mail@ny2k.com.au or book a consultation.
