# International Ring Size Chart

*Last updated: May 13, 2026*

## Ring Size Conversion Table

This comprehensive chart converts ring sizes between US, UK, EU, and Asian standards.

| US/Canada | UK/Australia | EU/Europe | Inside Diameter (mm) | Inside Circumference (mm) |
|-----------|--------------|-----------|---------------------:|--------------------------:|
| 3         | F            | 44        | 14.1                 | 44.2                      |
| 3.5       | G            | 45        | 14.5                 | 45.5                      |
| 4         | H            | 46        | 14.9                 | 46.8                      |
| 4.5       | I            | 48        | 15.3                 | 48.0                      |
| 5         | J            | 49        | 15.7                 | 49.3                      |
| 5.5       | K            | 50        | 16.1                 | 50.6                      |
| 6         | L            | 51        | 16.5                 | 51.8                      |
| 6.5       | M            | 52        | 16.9                 | 53.1                      |
| 7         | N            | 54        | 17.3                 | 54.4                      |
| 7.5       | O            | 55        | 17.7                 | 55.6                      |
| 8         | P            | 56        | 18.1                 | 56.9                      |
| 8.5       | Q            | 58        | 18.5                 | 58.1                      |
| 9         | R            | 59        | 18.9                 | 59.5                      |
| 9.5       | S            | 60        | 19.4                 | 60.8                      |
| 10        | T            | 62        | 19.8                 | 62.1                      |
| 10.5      | U            | 63        | 20.2                 | 63.4                      |
| 11        | V            | 64        | 20.6                 | 64.6                      |
| 11.5      | W            | 66        | 21.0                 | 65.9                      |
| 12        | X            | 67        | 21.4                 | 67.2                      |
| 12.5      | Y            | 68        | 21.8                 | 68.5                      |
| 13        | Z            | 70        | 22.2                 | 69.7                      |

## How to Use This Chart

1. **If you know your size in one system**: Find your size in that column and read across to find the equivalent in other systems.

2. **If you have a ring to measure**: Measure the inside diameter in millimeters, then find the closest match in the diameter column.

3. **If measuring your finger**: Wrap a strip of paper around your finger, mark where it overlaps, and measure the length in millimeters. Find this measurement in the circumference column.

## Regional Standards

- **US/Canada**: Numerical system (3-13+), most common in North America
- **UK/Australia**: Letter system (A-Z), used in British Commonwealth countries
- **EU/Europe**: Numerical system based on circumference in mm, used across Europe
- **Asian sizes**: Often similar to EU but may vary by country

## Important Notes

- Half sizes are available in most systems
- Ring width affects fit - wider bands typically need a larger size
- Finger size varies throughout the day and with temperature
- When between sizes, round up for wider bands, down for narrow bands

## Related Pages

- [Home](/) - Interactive ring sizer tool
- [Understanding Ring Size](/resources/understanding-ring-size) - Complete sizing guide