Find your BröKoss ring size quickly and avoid confusing ring-size numbers with measurement units. You can estimate the size from the inside diameter of a ring you already own or from finger circumference, then compare Spain, France/EU and US sizing systems.
Important: ring size numbers are not inches.
US sizes such as 7, 8 or 8.5 are ring-size numbers — they do not mean 7, 8 or 8.5 inches.
When using the calculator below, enter the physical measurement in millimetres (mm). If your ruler or tape measure is in inches, convert it first: 1 inch = 25.4 mm.
The most reliable way to find your ring size: use a ring sizer
If the ring is for you and you do not already know your size, our preferred method is to use a physical ring sizer. It lets you check not only the number itself, but also how the ring passes over the knuckle and how it actually feels once it is sitting on the finger.
Try the most likely size, then compare the size immediately above and below it. The correct fit should pass over the knuckle with slight resistance and then sit securely without feeling painfully tight or spinning continuously.
Ring sizer and ring mandrel are not the same tool. A ring sizer is a set of sample rings worn directly on the finger. A ring mandrel, shown further down this guide, is used to measure the size of an existing ring.
Ring size calculator
Choose what you were able to measure. For the most reliable result, use a ring that already fits the intended finger and measure the inside opening precisely.
Measure the inside opening from one inner edge to the other, straight across the centre.
Enter millimetres (mm) only. Using inches? Convert first: inches × 25.4 = mm. Example: 0.71 in ≈ 18.0 mm.
International ring size conversion chart
Ring-sizing systems are different from country to country. The table below compares the BröKoss / Spain size, the France / EU size, the approximate inside diameter in millimetres and an approximate US ring size.
Why “US approx.”? International systems do not convert perfectly one-to-one, and published conversion charts can vary slightly. The physical measurement in millimetres is therefore the best reference when you are unsure.
| BröKoss / Spain ring size | France / EU ring size | Inside diameter (mm) | US ring size approx. |
|---|---|---|---|
| 7 | 47 | 14.96 | 4 |
| 8 | 48 | 15.28 | 4.5 |
| 9 | 49 | 15.60 | 4.75 |
| 10 | 50 | 15.92 | 5.25 |
| 11 | 51 | 16.23 | 5.75 |
| 12 | 52 | 16.55 | 6 |
| 13 | 53 | 16.87 | 6.25 |
| 14 | 54 | 17.19 | 6.75 |
| 15 | 55 | 17.51 | 7.25 |
| 16 | 56 | 17.83 | 7.5 |
| 17 | 57 | 18.14 | 8 |
| 18 | 58 | 18.46 | 8.25 |
| 19 | 59 | 18.78 | 8.75 |
| 20 | 60 | 19.10 | 9 |
| 21 | 61 | 19.42 | 9.5 |
| 22 | 62 | 19.74 | 10 |
| 23 | 63 | 20.05 | 10.25 |
| 24 | 64 | 20.37 | 10.75 |
| 25 | 65 | 20.69 | 11 |
| 26 | 66 | 21.01 | 11.5 |
| 27 | 67 | 21.33 | 11.75 |
| 28 | 68 | 21.65 | 12.25 |
| 29 | 69 | 21.96 | 12.5 |
| 30 | 70 | 22.28 | 13 |
| 31 | 71 | 22.60 | 13.25 |
| 32 | 72 | 22.92 | — |
| 33 | 73 | 23.24 | — |
For EU sizes above 71, US equivalents can vary more between conversion charts. If you need one of these larger sizes, contact us and we will help you confirm it before ordering.
How to measure a ring you already own
- Choose a ring that already fits the finger where the new ring will be worn.
- Place it flat on a ruler.
- Measure only the inside diameter, not the outer edges of the ring.
- Measure straight across the centre.
- Enter that number in the calculator above in millimetres.
Example: if the inside diameter is approximately 18.1 mm, the result is around EU 57 / BröKoss-Spain 17 / US 8.
How to measure finger circumference
Wrap a narrow strip of paper or a non-stretch measuring tape around the finger where the ring will be worn. It should feel snug but still be able to pass over the knuckle. Mark the point where the ends meet and measure the length in millimetres.
Finger size can vary with temperature and time of day, so measuring more than once can improve accuracy. Wide rings can also feel tighter than narrow rings, so if you are between two sizes, ask us before ordering.
How should a correctly sized ring fit?
A well-fitting ring should feel secure and comfortable. It should not fall off or spin constantly, but it should not create intense pressure or pain either.
- It should stay in position without moving excessively.
- It should pass over the knuckle with slight resistance.
- A light temporary mark can be normal, but the ring should not feel painful or restrictive.
- If it spins constantly or feels as though it may fall off, it is probably too large.
Finger volume can change slightly during the day. Try to measure when your hands are at a normal temperature, not immediately after exercise or exposure to extreme heat or cold.
Using a ruler in inches?
Do not type the inch value directly into the calculator. Convert it to millimetres first.
Formula: inches × 25.4 = millimetres.
For example, 0.75 inches = 19.05 mm.
How to measure an existing ring with a ring mandrel
If you have access to a jeweller’s ring mandrel, slide an existing ring that already fits correctly onto the mandrel until it rests naturally. Read the size at the point that aligns with the inside edge of the ring.
Do not force the ring down the mandrel. The correct reading is where the ring naturally comes to rest.
Choosing a surprise ring for someone else
If the ring is a surprise and you do not know his exact size, try to discreetly borrow a ring he already wears on the same or a similar finger. Measure its inside diameter and use the calculator above.
If you are still unsure, send us the measurement and tell us which BröKoss ring you are considering. We can help you interpret the measurement before you order.
Still unsure about the size?
Send us the measurement or a photo of the ring you used as a reference. We are available on WhatsApp 365 days a year.
Ask us on WhatsApp View men’s engagement ringsSize exchange: if the chosen size is not right, the size exchange itself is free; only shipping costs are payable.
