Enter the ring diameter or finger circumference, select the measurement system, and click "Calculate" — the converter will instantly display the corresponding sizes according to Ukrainian, European (EU), US, UK, and Japanese (JP) ring size standards.
Calculator
How to measure your ring size properly
An accurate size ensures that the ring will fit perfectly and you won't have to return it. Here are some practical rules:
- Measuring with string or paper. Wrap a piece of string or paper strip around your finger where you plan to wear the ring. Mark where the ends meet, lay it flat, and measure the length with a ruler. This is your finger circumference in millimeters — the basis for calculation in most international standards.
- Choose the right time. In the morning and after physical activities, fingers can be swollen or, conversely, shrink in the cold. The most accurate result is in the middle of the day, at room temperature.
- Consider the width of the ring. If the ring is wide (over 6 mm), go up half a size. A wide band fits the finger more tightly than a thin one of the same number.
What do different size standards mean?
- Ukraine and CIS countries (UA/RU). The size equals the inner diameter of the ring in millimeters. A size 17 ring has an inner diameter of 17 mm. This is the simplest standard to understand.
- European Standard (EU). The size corresponds to the inner circumference of the ring in millimeters. For example, EU 53 means a circumference of 53 mm, which corresponds to a diameter of 17 mm.
- United States (US). The size is designated by a numerical scale from 1 to 13+, where each size corresponds to a specific diameter. It has no direct logical connection to millimeters, so a table is indispensable.
- United Kingdom (UK). The size is determined by an alphabetical scale from A to Z+. Each letter (sometimes marked with ½) corresponds to a specific circumference. It covers a wide range and is also used in Australia and New Zealand.
- Japan (JP). The size is also designated by a numerical scale similar to the US scale, but with its own values. Japanese sizes are usually slightly larger than American ones for the same finger.
Ring Size Correspondence Table
| Diameter (UA/RU) | Circumference (EU) | USA (US) | Britain (UK) | Japan (JP) |
|---|---|---|---|---|
| 14.0 mm | 44.0 mm | 3.00 | F | 4 |
| 14.5 mm | 45.6 mm | 3.50 | G | 5 |
| 15.0 mm | 47.1 mm | 4.25 | H½ | 7 |
| 15.5 mm | 48.7 mm | 4.75 | I½ | 8 |
| 16.0 mm | 50.3 mm | 5.50 | K | 10 |
| 16.5 mm | 51.8 mm | 6.00 | L | 11 |
| 17.0 mm | 53.4 mm | 6.50 | M | 13 |
| 17.5 mm | 55.0 mm | 7.25 | N½ | 14 |
| 18.0 mm | 56.5 mm | 7.75 | O½ | 16 |
| 18.5 mm | 58.1 mm | 8.50 | Q | 17 |
| 19.0 mm | 59.7 mm | 9.00 | R | 19 |
| 19.5 mm | 61.3 mm | 9.75 | S½ | 20 |
| 20.0 mm | 62.8 mm | 10.25 | T½ | 22 |
| 20.5 mm | 64.4 mm | 11.00 | V | 23 |
| 21.0 mm | 66.0 mm | 11.50 | W | 25 |
| 21.5 mm | 67.5 mm | 12.25 | Y | 26 |
| 22.0 mm | 69.1 mm | 12.75 | Z | 28 |
Frequently Asked Questions (FAQ)
- What is the most common ring size?
For women, the most common sizes range from 16 to 18 mm (EU 50–56, US 5–8). For men, they range from 19 to 22 mm (EU 59–69, US 9–12). However, this is just statistics: the size depends on the specific person, so measurements are always more accurate than average values. - Can I determine my ring size from an existing ring?
Yes. Place the ring on a piece of paper, trace the inner circle, and measure the diameter of the resulting circle with a ruler — this will be your size according to the Ukrainian standard. Alternatively, measure the inner circumference with a thread to get the EU size. - What should I do if my finger size is between two values?
If the ring is thin (up to 4 mm), choose the smaller size so it won't spin. If it's wide (6 mm and more), choose the larger one, as a wide band fits tighter. When in doubt, it is better to choose the larger size: a slightly loose ring is more comfortable than one that's too tight. - Does the ring size differ for different fingers?
Yes, and sometimes significantly. The ring finger of the left and right hand can differ by a whole size. If you are buying a wedding band, measure the exact finger of the hand on which you plan to wear the ring. - Why are sizes in different countries so different, and is there a single international standard?
There is no single standard. Each system has evolved historically: the metric one (UA/EU) is based on the geometry of the ring, while the American and British ones are based on their own trade traditions. This is why a converter between standards is not a luxury but a practical necessity, especially when buying jewelry from foreign online stores.