Ring Size Converter
Convert ring size (US/Canada,UK,Diameter (mm),Circumference (mm)) instantly in your browser — nothing uploaded.
| US/Canada | UK | Diameter (mm) | Circumference (mm) |
|---|---|---|---|
| 3 | F | 14.1 | 44.2 |
| 4 | H | 14.9 | 46.8 |
| 5 | J | 15.7 | 49.3 |
| 6 | L | 16.5 | 51.9 |
| 7 | N | 17.3 | 54.4 |
| 8 | P | 18.1 | 57 |
| 9 | R | 18.9 | 59.5 |
| 10 | T | 19.8 | 62.1 |
| 11 | V | 20.6 | 64.6 |
| 12 | X | 21.4 | 67.2 |
| 13 | Z | 22.2 | 69.7 |
Based on a widely-cited jewelry industry chart. For an exact fit, use a physical ring sizer — finger size can vary slightly throughout the day.
How the Ring Size Converter Works
Converts jewelry ring sizes across US/Canada, UK/Australia/NZ, EU, and Japanese standards using inside diameter and circumference in millimeters.
Conversion Example
A US size 7 ring has an inside diameter of 17.3 mm, equivalent to a UK size N and EU size 54.
Frequently Asked Questions
How do you measure ring size?
Ring sizes map directly to the inner circumference (in mm for the EU system) or the inner diameter.