How to find your ring size at home (and why we'd still rather size you)
The most reliable way to find your ring size at home is to measure the inside diameter of a ring you already wear on that finger and read it off the chart below. Australian sizes are letters (K, L, M), American sizes are numbers, and the only measurement that means the same thing everywhere is millimetres. Here is the chart, the methods that work, and where they fall down.
The ring size chart: Australian letters, US numbers and millimetres
Australia, the United Kingdom and New Zealand share the same letter system. The United States uses numbers. The two systems do not line up exactly, so the US column is a close equivalent rather than a perfect match. Inside diameter is the width across the inside of the ring; circumference is the distance around the inside.
| AU / UK | US | Inside diameter | Circumference |
|---|---|---|---|
| H | 4 | 14.9 mm | 46.8 mm |
| I | 4½ | 15.3 mm | 48.0 mm |
| J | 4¾ | 15.5 mm | 48.7 mm |
| J½ | 5 | 15.7 mm | 49.3 mm |
| K | 5¼ | 15.9 mm | 49.9 mm |
| K½ | 5½ | 16.1 mm | 50.6 mm |
| L | 5¾ | 16.3 mm | 51.2 mm |
| L½ | 6 | 16.5 mm | 51.9 mm |
| M | 6¼ | 16.7 mm | 52.5 mm |
| M½ | 6½ | 16.9 mm | 53.1 mm |
| N | 6¾ | 17.1 mm | 53.8 mm |
| N½ | 7 | 17.3 mm | 54.4 mm |
| O | 7¼ | 17.5 mm | 55.1 mm |
| O½ | 7½ | 17.7 mm | 55.7 mm |
| P | 7¾ | 17.9 mm | 56.3 mm |
| P½ | 8 | 18.1 mm | 57.0 mm |
| Q | 8¼ | 18.3 mm | 57.6 mm |
| Q½ | 8½ | 18.5 mm | 58.3 mm |
| R | 8¾ | 18.7 mm | 58.9 mm |
| S | 9¼ | 19.2 mm | 60.2 mm |
| T | 9¾ | 19.6 mm | 61.4 mm |
The most common women's engagement ring sizes in Australia are L to N. The most common men's wedding band sizes are T to V. Half sizes are real sizes, not rounding: the difference between M and M½ is what separates a ring that spins from one that sits still.
Method one: measure a ring you already wear
This is the method we trust most. Take a ring that is worn on the same finger of the same hand; the left and right ring fingers can differ by half a size. Lay it on a ruler and measure straight across the inside, from inner edge to inner edge, at the widest point. Read the millimetres off the chart. If the ring is not perfectly round, measure twice and average. If it lands between sizes, note both.
Method two: string or a strip of paper
Wrap a strip of paper around the base of the finger, mark where it overlaps, and measure the length against the circumference column. It works, with caveats. String stretches; paper does not, so prefer paper. Pull it snug, not tight. It must also pass back over the knuckle, so check that it does. Most people measure themselves half a size to a full size small this way, because a strip of paper does not behave like a band of metal. Treat the result as a range.
Method three: a plastic sizing gauge
An inexpensive plastic ring gauge is a step up from string because it is a solid loop that behaves like a ring. Printable paper sizers are the least reliable of all: they depend on the page printing at exactly 100 per cent scale, which many printers quietly do not do.
Things that change your size from one day to the next
- Temperature. Cold fingers shrink, sometimes by a full size. Do not measure straight after a cold morning walk.
- Time of day. Fingers are smallest first thing and largest in the evening. Late afternoon at room temperature is about right.
- Heat, salt and exercise all swell the fingers. Pregnancy does too, for longer.
- Knuckles. If the knuckle is noticeably larger than the base of the finger, the ring has to pass over it. The right size is a compromise between the two, and we can help with that.
Wide bands need a bigger size
A band wider than about 5 mm sits on more of the finger and feels tighter than a slim band of the same size. Most people go up half a size for a wide band. Bands with a rounded, comfort-fit interior sit differently again. This matters when you are choosing a wedding band to sit against an engagement ring; our guide to pairing a wedding band covers the fit, and the wedding bands page shows the widths.
Sizing for a surprise proposal
If you are proposing with a finished ring, you are guessing to some degree. These are the guesses that work best:
- Borrow a ring she already wears, on the ring finger of the left hand if possible. Measure the inside as above, or press it into a bar of soap and measure the impression. A ring worn on the right hand, or another finger, is a clue, not an answer, but note which finger it came from and we can adjust.
- Ask a friend, sister or mother. Someone usually knows, or can find out over a coffee without giving anything away.
- Check the box or receipt of a ring she owns; sizes are often written there.
- When you are torn between two sizes, choose the larger. A ring that goes on can be sized down. A ring that does not go on cannot be tried.
Our own answer to the surprise problem is simpler: propose with the ring at your best guess, then bring her in afterwards and we size it properly. The first resize is complimentary on every ring we make.
Why we would still rather size you
A steel gauge in the boutique, on your hand, at normal temperature, matched to the width and profile of the design you have chosen, takes five minutes and removes every caveat above. It also lets us check how the engagement ring and wedding band will sit together, which a single measurement cannot. There is no obligation and no appointment needed for a quick fitting; if you would like time with the rings as well, book a private viewing.
Made to order, and the first resize is on us
Every ring in our engagement collection is made to order in your size. Sizes H to P are listed on each product page; sizes above P may carry a small additional charge for the extra metal, which we confirm when we quote. If the size changes later, the first resize is complimentary. A few designs, such as full eternity bands and some channel-set bands, cannot be resized far without remaking them; we will tell you that before you choose, not after. Our care and servicing guide covers what to expect over the years.
Not sure of your size? Book a private viewing and we will measure you properly, with the rings in front of you.
