Ring Size Guide
Choosing the right ring size matters as much as choosing the right diamond. This guide shows you three reliable ways to measure a ring size at home, a full international conversion chart, the mistakes that skew results, and what to do if the size still isn't perfect.
Three ways to find the right size
1. Measure a ring she already wears
Take a ring worn on the intended finger, place it on a ruler and measure the inner diameter in millimetres — edge to edge at the widest point. Then find the matching size in the chart below. This is the most discreet method for a surprise proposal.
No time to measure? Press the ring gently into a bar of soap and photograph the imprint next to a coin for scale, or trace the inner circle on paper several times and take the average.
2. Measure the finger
Wrap a thin strip of paper or a piece of string around the base of the finger, mark where it overlaps and measure the length in millimetres. That number is the circumference — in the EU sizing used at ORIZIANO, the circumference in millimetres is the ring size itself.
3. Ask us for help
Write to us at eshop@oriziano.com. We will guide you through the measurement or help you estimate the size from a photo of a ring placed on a ruler.
International ring size chart
| EU size (circumference in mm) | Inner diameter (mm) | US | UK |
|---|---|---|---|
| 47 | 15.0 | 4 | H½ |
| 48 | 15.3 | 4½ | I½ |
| 49 | 15.6 | 4¾ | J½ |
| 50 | 15.9 | 5¼ | K |
| 51 | 16.2 | 5¾ | L |
| 52 | 16.6 | 6 | L½ |
| 53 | 16.9 | 6¼ | M½ |
| 54 | 17.2 | 6¾ | N½ |
| 55 | 17.5 | 7¼ | O |
| 56 | 17.8 | 7½ | P |
| 57 | 18.1 | 8 | P½ |
| 58 | 18.5 | 8¼ | Q½ |
| 59 | 18.8 | 8¾ | R |
| 60 | 19.1 | 9 | R½ |
| 61 | 19.4 | 9½ | S½ |
| 62 | 19.7 | 10 | T½ |
| 63 | 20.1 | 10¼ | U |
| 64 | 20.4 | 10¾ | V |
| 65 | 20.7 | 11 | V½ |
| 66 | 21.0 | 11½ | W½ |
| 67 | 21.3 | 11¾ | X |
| 68 | 21.6 | 12¼ | Y |
| 69 | 22.0 | 12½ | Z |
| 70 | 22.3 | 13 | Z+1 |
Conversions are approximate — sizing standards overlap slightly between systems. When in doubt, choose the larger size: making a ring smaller is easier than making it larger.
What is the most common ring size?
The most common women's sizes in Europe are 52 to 54 (US 6 to 6¾); for men, 60 to 62 (US 9 to 10). If you have no way to measure and you are planning a surprise, EU 53 is the statistically safest choice for a woman's ring.
Treat that as a last resort, though. The difference between 52 and 55 is noticeable straight away, and a resize delays delivery.
The mistakes that skew measurements
- Measuring in the morning or in the cold. Fingers are at their smallest then. Measure in the evening, when they are their true size.
- Ignoring the knuckle. If the knuckle is noticeably wider than the base of the finger, measure both and pick a size in between. The ring has to pass over the knuckle without spinning freely afterwards.
- Wide bands. Add half a size from 3 mm, a full size above 6 mm.
- The wrong hand. The dominant hand tends to be half a size larger.
Proposing and can't measure at all?
Order EU 53 and we will sort out any adjustment after the proposal. Most gold rings can be resized by one to two sizes, so having the ring in your hand at the right moment matters more than perfect precision beforehand.
Size still not perfect? Every ORIZIANO jewel is made to order in Valenza — and we stay with you after the purchase. If the size doesn't fit, contact us at eshop@oriziano.com and we will arrange a resize for you.
Frequently asked questions
What ring size does an average woman in Europe wear?
The most common women's sizes in Europe are EU 52–54 (US 6–6¾). If you have no way to measure, EU 53 is the statistically safest choice for a surprise.
How do I secretly find out a ring size for a proposal?
Borrow a ring she wears on the ring finger and measure its inner diameter, press it into a bar of soap and photograph the imprint next to a coin, or ask her family or friends — they are often surprisingly well informed.
How do I find a ring size without a measuring tape?
Use a strip of paper or a piece of string: wrap it around the finger, mark the overlap, straighten it out and hold it against a ruler.
What is the difference between ring size and diameter?
The European size is the circumference of the finger in millimetres. The diameter is the width of the circle measured across — roughly 3.14 times smaller. An inner diameter of 17.2 mm corresponds to size 54.
What if my size falls between two numbers?
Choose the larger one. Making a ring smaller is easier, cheaper and gentler on the jewel than making it larger, especially with stones set around the band.
Can the size of a ring be adjusted later?
Yes. Most gold rings can be resized by a skilled goldsmith, typically within one to two sizes. With stones set all the way around the band it depends on the model — contact us and we will tell you exactly what is possible for your piece.
Ready to choose? Browse our engagement rings with lab-grown diamonds or read our complete lab-grown diamond guide.