You can find your ring size tonight with a strip of paper, a pen and a ruler. Cut the paper about 10 cm long, wrap it snugly around the base of the finger, and mark where the end overlaps. Lay it flat and measure from the end to the mark in millimetres. That number is your finger's circumference. It is also your EU ring size. The chart below turns it into a US size, an NZ letter, or the right pick on a Rivendell ring page.
Ring sizes look like three different languages. New Zealand jewellers use letters, Rivendell's sterling silver rings use US numbers, and Europe uses millimetres. They all describe the same thing: the distance around the inside of the ring. Once you have that in millimetres, every other system is one look-up away.
On this page: the paper method · measure a ring you own · the conversion chart · Rivendell sizes · tips · FAQ
How do you measure your ring size with paper or string?
This is the method for anyone who has no ring to copy, or who is buying for someone else. Paper works better than string, because string stretches a little when you pull it.
- Cut a thin strip of paper about 10 cm long. A ribbon of printer paper is perfect.
- Wrap it around the base of the finger where the ring will sit. Snug, not tight. It should still slide over the knuckle.
- Mark with a pen where the end overlaps the strip.
- Unwrap it and measure from the end to your mark, in millimetres. That is your circumference.
- Read your size from the chart below. Between two sizes? Take the larger one.
Do it three times and use the middle result. Fingers change through the day, so if the three numbers wander, measure again in the evening.
🔮 Already have a ring that fits? Measure that instead
If a ring already sits happily on the right finger, measure the ring rather than the finger. Lay it on a ruler and read the inside width from inner edge to inner edge. That is the inside diameter, and the chart has a column for it.
Want the circumference instead? Multiply the diameter by 3.14. A ring with a 17.3 mm inside reads as 54 mm around, which is a US 7. Going the other way, divide your paper measurement by 3.14 to get the diameter.
Two small warnings. Measure a ring from the same finger on the same hand, because sizes differ between fingers and between hands. And measure round rings only. Open bands and twisted bands squash slightly, so use the paper method for those.
✨ Ring size conversion chart: mm to US, NZ/UK and EU
Find your circumference or your diameter in the first two columns, then read across. The EU size is simply the circumference rounded to a whole millimetre. Quick lookup for a strip that reads a round number: 50 mm is just under a US 5½ (K), 55 mm just under a US 7½ (O), 60 mm just over a US 9 (R), 65 mm just over a US 11 (V).
| US size | Inside diameter | Circumference | NZ / UK / AU | EU / ISO |
|---|---|---|---|---|
| 4 | 14.9 mm | 46.8 mm | H | 47 |
| 4½ | 15.3 mm | 48.1 mm | I | 48 |
| 5 | 15.7 mm | 49.3 mm | J | 49 |
| 5½ | 16.1 mm | 50.6 mm | K | 51 |
| 6 | 16.5 mm | 51.8 mm | L | 52 |
| 6½ | 16.9 mm | 53.1 mm | M | 53 |
| 7 | 17.3 mm | 54.3 mm | N | 54 |
| 7½ | 17.7 mm | 55.6 mm | O | 56 |
| 8 | 18.1 mm | 56.9 mm | P | 57 |
| 8½ | 18.5 mm | 58.1 mm | Q | 58 |
| 9 | 19.0 mm | 59.7 mm | R | 60 |
| 9½ | 19.4 mm | 60.9 mm | S | 61 |
| 10 | 19.8 mm | 62.2 mm | T | 62 |
| 10½ | 20.2 mm | 63.5 mm | U | 64 |
| 11 | 20.6 mm | 64.7 mm | V | 65 |
| 11½ | 21.0 mm | 66.0 mm | W | 66 |
| 12 | 21.4 mm | 67.2 mm | X | 67 |
The millimetres come from the GIA international ring size chart, and Tiffany's official sizing guide gives the same diameters. One honest note about letters: NZ jewellers' charts sit about half a letter apart from each other, so a US 7 shows as N on some and N½ on others. If you only know your letter, trust the millimetres more than the letter.
The EU system is the tidy one. The international standard, ISO 8653, defines a ring size as the inside circumference in millimetres, so a size 54 ring is 54 mm around. That is why the paper strip is such a good tool: it gives you an EU size with no conversion at all.
💎 Which size do I pick on a Rivendell ring page?
Every sterling silver ring at Rivendell is sized in US numbers, from 5 to 10. Take your circumference from the paper strip, or your diameter from a ring, and pick the row it lands on. Land between two rows? Take the larger size.
| Rivendell size | Inside diameter | Circumference | NZ letter |
|---|---|---|---|
| US 5 | 15.7 mm | 49.3 mm | J |
| US 6 | 16.5 mm | 51.8 mm | L |
| US 7 | 17.3 mm | 54.3 mm | N |
| US 8 | 18.1 mm | 56.9 mm | P |
| US 9 | 19.0 mm | 59.7 mm | R |
| US 10 | 19.8 mm | 62.2 mm | T |
Our delicate rings are narrow bands, so your measured size is the one to order. Dressier rings with a wider shank fit more snugly, and half a size up is kinder. If you are choosing a stone rather than a size, the silver ring meaning guide and the crystal ring personality guide will help.
Copper is different. The Twist Copper Ring comes in Small, Medium and Large, and the listing gives each as an inside diameter. Here is where those sizes land on the chart.
| Copper size | Inside diameter | Circumference | Close to |
|---|---|---|---|
| Small | 16 mm | 50.3 mm | US 5½, NZ K |
| Medium | 17.5 mm | 55.0 mm | US 7 to 7½, NZ N to O |
| Large | 19 mm | 59.7 mm | US 9, NZ R |
If your circumference sits between Small and Medium, choose Medium. If you wear copper on the wrist as well, the same paper trick works around the wrist; our guide to wearing copper bracelets covers fit and which wrist.
🌙 Small tips that make the measurement right
Measure in the evening. Fingers shrink in the cold and swell in the heat, so a cool morning reading can come out smaller than an evening one. Warm hands after dinner give the truest fit.
Mind the knuckle. A ring has to pass the knuckle and then sit still. If your knuckle is much bigger than the base of the finger, measure both and choose a size in between.
Wide bands run small. A wide shank covers more finger and feels tighter than a thin one. Go up half a size for anything chunky.
Round up, not down. If you sit between two sizes, take the larger. A slightly loose ring wears happily; a tight one lives in a drawer.
Measure the actual finger. Sizes differ between fingers and between hands, so measure the exact finger the ring is for.
Buying a secret gift? Borrow a ring from the finger they wear it on, trace the inside circle on paper, and measure the circle's width. Then round up. The choosing silver rings guide has more on picking a style that forgives a half-size guess.
💎 Choosing a piece
Once the size is settled, the fun part is the stone. Delicate rings put one small faceted stone in a plain bezel and suit stacking. Stone rings carry a bigger cabochon and make a single statement. A moonstone ring glows softly beside plain silver (the moonstone meaning guide tells its story); a labradorite ring flashes blue when the light moves. If you like choosing by star sign, the zodiac silver guide matches stones to birthdays.
Live shop prices, September 2026. They move a little over time.
| Ring | Sizes | Price |
|---|---|---|
| Twist Copper Ring | Small, Medium, Large | NZ$20 |
| Citrine Delicate 925 Sterling Silver Ring | US 5 to 10 | from NZ$35 |
| Smoky Quartz Delicate 925 Sterling Silver Ring | US 5 to 10 | from NZ$35 |
| Labradorite Delicate 925 Sterling Silver Ring | US 5 to 10 | NZ$50 |
| Peridot Delicate 925 Sterling Silver Ring | US 5 to 10 | NZ$50 |
| Garnet Delicate 925 Sterling Silver Ring | US 5 to 10 | NZ$50 |
| Blue Topaz Delicate 925 Sterling Silver Ring | US 5 to 10 | NZ$50 |
| Amethyst ring, sterling silver | US 5 to 10 | NZ$75 |
| Moonstone ring, sterling silver | US 5 to 10 | NZ$85 |
| Labradorite ring, sterling silver | US 5 to 10 | NZ$85 |
Citrine and smoky quartz delicate rings are NZ$35 in one size and NZ$50 in the others, so the price depends on the size you pick. Each delicate ring comes with an elegant pouch, ready to give.
Everything posts from our Auckland shop. If you would rather try rings on before you choose, visit Rivendell at Shop 62, Westfield Manukau.
Size found? Pick the stone. ✨
See the sterling silver ringsRing size FAQ
What is the average ring size for women in NZ?
NZ jewellers say the most common women's sizes are M to N, which is US 6½ to 7, and the most common men's sizes are T to V, which is US 10 to 11. Big retailers overseas report the same picture: size 6 is the single most popular women's size and size 9 the most popular men's size.
What ring size is 45 mm?
A 45 mm circumference is about a US 3½, or NZ letter G. That is small for an adult finger, so check you measured around the finger and not across it. If you were measuring a wrist for a bangle or cuff, wrap the paper around the wrist instead and see our guide to wearing copper bracelets for fit.
What ring size is 6 cm?
6 cm is 60 mm around, which is just over a US 9 (59.7 mm) and an NZ letter R. Pick a 9, or a 9½ (60.9 mm, letter S) if you like more room. In the EU system it is simply size 60.
What ring size is 6.7 cm?
6.7 cm is 67 mm around, which is a US 12 and an NZ letter X. The EU size is 67.
Is the paper method accurate enough to buy a ring?
For a silver ring, yes, if you measure three times in the evening and round up. Paper stretches less than string. A jeweller's ring sizer is more exact, so for an engagement ring or a wide band, get sized in store first.
What if I am between two sizes?
Take the larger one. It is easier to make a ring smaller than bigger, and a ring that will not pass the knuckle is no ring at all. Titanium and tungsten rings cannot be resized, so with those the measurement has to be right first time.
Sources
- GIA 4Cs: How to determine ring size, with the international ring size chart — the diameters, circumferences and letters in the chart, plus the cold, knuckle and wide-band tips.
- Tiffany & Co. Ring Size Guide (PDF) — cross-check of US sizes against inside diameters.
- ISO 8653:2016, Jewellery — Ring-sizes (preview) — the definition of a ring size as the inside circumference in millimetres.
- Ring size — how the US and UK scales step, and the half-letter difference between charts.
- NZ Jewellers ring sizing guide and Michael Hill NZ ring size guide — common NZ sizes, the 10 cm strip and the resizing note.
- Blue Nile: How to measure your ring size — the 3.14 rule, end-of-day timing and the most popular sizes.
Last updated September 2026
1 comment
Beautiful