Buying a ring from another country means switching systems. UK sizes are letters, US sizes are numbers, and EU sizes are usually the ring's inner circumference in millimetres.
Ring size chart
These are common whole sizes. Half sizes sit in between, and different jewellers may differ by a fraction.
| UK | US | Diameter (mm) | Circumference (mm) |
|---|---|---|---|
| H½ | 4 | 14.9 | 46.8 |
| J½ | 5 | 15.7 | 49.3 |
| L½ | 6 | 16.5 | 51.8 |
| N½ | 7 | 17.3 | 54.4 |
| P½ | 8 | 18.1 | 57.0 |
| R½ | 9 | 18.9 | 59.5 |
| T½ | 10 | 19.8 | 62.1 |
EU ring sizes
European sizes are roughly the circumference in millimetres, so a 52 is about a 52 mm inner circumference. Check each jeweller's own chart, since some round to whole numbers.
How to measure at home
- Wrap a strip of paper or string around the base of the finger you will wear the ring on.
- Mark where it overlaps and measure the length in mm. That is your circumference.
- Match it to the chart above.
- Measure at the end of the day, when your hands are warm and fingers are at their largest.
Tips
- A wide band feels tighter than a thin band, so you may want a half size up.
- Fingers swell in heat and shrink in cold, so measure more than once.
- The knuckle can be larger than the base. The ring needs to pass over it.
Converting other sizes?
Our converter handles clothing and shoe sizes across UK, US, EU and more.
Open the size converter →