Ring Size Converter
Choose your sizing system and select your ring size to see equivalent sizes in all other systems.
Converted Sizes
| US | UK | EU | Ø mm | Circ mm |
|---|---|---|---|---|
| 3 | F | 44 | 14 | 44 |
| 3.5 | G | 45 | 14.4 | 45.2 |
| 4 | H | 46.5 | 14.8 | 46.5 |
| 4.5 | I | 47.8 | 15.2 | 47.8 |
| 5 | J | 49 | 15.6 | 49 |
| 5.5 | K | 50.3 | 16 | 50.3 |
| 6 | L | 51.5 | 16.5 | 51.8 |
| 6.5 | M | 52.8 | 16.9 | 53.1 |
| 7 | N | 54 | 17.3 | 54.4 |
| 7.5 | O | 55.3 | 17.7 | 55.7 |
| 8 | P | 56.5 | 18.1 | 57 |
| 8.5 | Q | 57.8 | 18.5 | 58.3 |
| 9 | R | 59 | 18.9 | 59.5 |
| 9.5 | S | 60.3 | 19.4 | 60.8 |
| 10 | T | 61.5 | 19.8 | 62.1 |
| 10.5 | U | 62.8 | 20.2 | 63.4 |
| 11 | V | 64 | 20.6 | 64.6 |
| 11.5 | W | 65.3 | 21 | 65.9 |
| 12 | X | 66.5 | 21.4 | 67.2 |
| 12.5 | Y | 67.8 | 21.8 | 68.5 |
| 13 | Z | 69 | 22.2 | 69.7 |
Ring Size Converter – International Ring Size Chart
Finding the right ring size can be confusing when shopping internationally. The US, UK, Europe, and Asia all use different sizing systems. This ring size converter instantly translates between US, UK/Australia, EU/International sizing, and millimeter measurements — making it easy to buy rings online or across borders.
How Ring Sizes Are Measured
Ring sizing systems differ by country, but they all relate to two physical measurements:
- Inner diameter: The distance across the inside of the ring in millimeters
- Inner circumference: The distance around the inside of the ring in millimeters
To find your ring size at home: Wrap a strip of paper or string snugly around your finger, mark where it overlaps, then measure the length in mm. That's your circumference — match it to the chart above.
Ring Sizing Systems Explained
US & Canada — Uses numerical half-sizes ranging from 3 to 13+. This is the most widely used system in North American jewelry stores.
UK & Australia — Uses alphabetical letters (F through Z). Each letter corresponds roughly to a half-size increment in the US system.
EU & International — Based on the inner circumference of the ring in millimeters. A common standard across Europe and many international retailers.
Asian sizes — Japan, China, and other Asian countries have their own systems, but EU/circumference sizing is increasingly adopted for online sales.
Ring Size Conversion Chart
| US | UK | EU | Diameter (mm) | Circumference (mm) |
|---|---|---|---|---|
| 4 | H | 46.5 | 14.8 | 46.5 |
| 5 | J | 49 | 15.6 | 49.0 |
| 6 | L | 51.5 | 16.5 | 51.8 |
| 7 | N | 54 | 17.3 | 54.4 |
| 8 | P | 56.5 | 18.1 | 57.0 |
| 9 | R | 59 | 18.9 | 59.5 |
| 10 | T | 61.5 | 19.8 | 62.1 |
| 11 | V | 64 | 20.6 | 64.6 |
| 12 | X | 66.5 | 21.4 | 67.2 |
| 13 | Z | 69 | 22.2 | 69.7 |
Tips for Accurate Ring Sizing
- Measure at the right time: Fingers swell during hot weather and shrink in cold. Measure in the afternoon at room temperature for the most accurate result.
- Consider ring width: Wide bands (6mm+) fit tighter, so you may need to go up a half-size.
- Dominant hand is larger: Your dominant hand is typically slightly larger than your other hand.
- Between sizes?: Go up to the next half-size, especially for rings you'll wear daily.
- Knuckle sizing: If your knuckle is significantly wider than your finger base, measure at the knuckle and go down half a size for comfort.
Average Ring Sizes
| Category | Average US Size | Average EU Size | Average Diameter |
|---|---|---|---|
| Women | 6 – 7 | 51.5 – 54 | 16.5 – 17.3 mm |
| Men | 9 – 11 | 59 – 64 | 18.9 – 20.6 mm |
Frequently Asked Questions
What is the most common ring size for women?
The most common ring size for women is US 6 to 7, which corresponds to EU 51.5–54 and UK L–N. However, individual sizes vary widely, so it's always best to measure.
What is the most common ring size for men?
The most common ring size for men is US 9 to 11, which corresponds to EU 59–64 and UK R–V.
How do I measure my ring size at home?
Wrap a thin strip of paper or string around your finger, mark where it overlaps, then measure the length. That's your circumference in mm. Match it to a size chart. Alternatively, measure the inner diameter of a ring that fits well.
Can ring size change over time?
Yes. Weight changes, pregnancy, arthritis, temperature, and humidity can all affect finger size. It's a good idea to re-measure periodically, especially before buying an expensive ring.
How do I convert my US ring size to EU?
Use the converter above. For example, US 7 = EU 54, US 8 = EU 56.5, US 9 = EU 59. The EU system is based on the inner circumference in millimeters.
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