Ring Sizing
Ring Size Chart Australia
Australian ring size chart: AU/UK letters H to Z+3 converted to US sizes, inside diameter and circumference in mm, plus how to measure at home and which size…
Australian and UK ring sizes are letters (H to Z+3). US sizes are numbers (4 to 14). The chart below converts between them and gives the inside diameter and circumference in millimetres, so you can match a ring you already own or a measurement from a jeweller. Every Helix product page lists both, for example 10 / T½.
The most reliable way to size a Helix ring is our free ring sizer. The sizer itself is free; standard postage applies if you order it on its own.
Ring size chart: AU/UK letters, US sizes and millimetres
| AU / UK size | US size | Inside diameter (mm) | Circumference (mm) |
|---|---|---|---|
| H | 4 | 15.3 | 48 |
| J | 5 | 15.7 | 49 |
| K | 5.5 | 16.1 | 51 |
| L | 6 | 16.5 | 52 |
| M | 6.5 | 16.9 | 53 |
| N½ | 7 | 17.35 | 55 |
| O | 7.5 | 17.75 | 56 |
| P | 8 | 18.2 | 57 |
| Q | 8.5 | 18.5 | 58 |
| R½ | 9 | 18.9 | 59 |
| S½ | 9.5 | 19.4 | 61 |
| T½ | 10 | 19.85 | 62 |
| U½ | 10.5 | 20.2 | 63 |
| V½ | 11 | 20.7 | 65 |
| W½ | 11.5 | 21.1 | 66 |
| Y | 12 | 21.5 | 68 |
| Z | 12.5 | 21.9 | 69 |
| Z+1 | 13 | 22.3 | 70 |
| Z+2 | 13.5 | 22.75 | 71 |
| Z+3 | 14 | 23.2 | 72 |
Circumference is the distance around the inside of the ring. Diameter is the straight line across the inside. Australian letter sizes move in very small steps, which is why two jewellers can hand you two different letters for the same finger.
How to measure your ring size at home
- Wrap the string. Wrap a piece of string or a strip of paper around the base of the finger you want to size, snug but not tight.
- Mark the overlap. Mark the point where the string meets itself with a pen.
- Measure. Lay the string flat and measure the marked length in millimetres. That is your circumference.
- Match to the chart. Find the circumference above and read across for the AU/UK letter and US size. If you land between two rows, choose the larger size for wide bands.
Measuring a ring you already own works too: measure the inside diameter in millimetres and read across from the diameter column.
Which ring size should I order?
- Wide bands (8 mm and 9 mm) fit tighter than thin ones. Most people go up half a size for a wide band.
- Helix metal rings are comfort fit, so the inside is rounded. If you are used to a flat inside band you may need half a size smaller.
- Fingers swell during the day and in warm weather. Try a sizer first thing in the morning and again after work before you decide.
- Silicone stretches slightly and should sit snug, not loose. If you are between sizes in silicone, choose the smaller one.
Ready to choose? Browse Men’s Silicone Rings, Women’s Silicone Rings or Silicone Wedding Rings, or start at the full Silicone Rings Australia range.
Common ring sizing questions
What is ring size J, N, Q or H in millimetres?
J is 49 mm around and 15.7 mm across (US 5). N½ is 55 mm around and 17.35 mm across (US 7). Q is 58 mm around and 18.5 mm across (US 8.5). H is 48 mm around and 15.3 mm across (US 4). Use the chart above for the rest of the scale.
Three jewellers gave me three different sizes. Which one is right?
Australian letter sizes move in tiny steps, and measuring tools and technique differ between shops, so small disagreements are normal. Size with the tool from the place you are buying from. For Helix that is our free ring sizer, which is why we recommend it over a jeweller’s reading.
What if I order the wrong size or it is a gift?
In-stock rings can be exchanged within 60 days of delivery under our returns and exchanges policy. Custom titanium rings are made to order and have their own shorter window and a remake fee, so size those with the sizer before you order.
What is the average ring size for men and women in Australia?
The most common men’s size we sell is US 10 (T½). For women it is around US 6 (L). If the ring is a gift and you cannot measure, order close to those sizes and use the exchange window if it does not fit.
Can Helix rings be resized?
Silicone, titanium and tungsten cannot be resized the way gold can. The fix for a wrong size is an exchange rather than a resize, so measure first. A free plastic sizer comes in the box with our stocked titanium and tungsten rings (and is posted out first for custom titanium), so you can check the replacement size before you exchange. Silicone rings do not include one, but anyone can order our free ring sizer.