Ring size conversion chart
| US | UK | EU | Japan | Diameter (mm) | Circumference (mm) |
|---|---|---|---|---|---|
| 4 | H | 46.5 | 7 | 14.9 | 46.8 |
| 4.5 | I | 47.5 | 8 | 15.3 | 48.0 |
| 5 | J | 49 | 9 | 15.7 | 49.3 |
| 5.5 | K | 50 | 10 | 16.1 | 50.6 |
| 6 | L | 51.5 | 11 | 16.5 | 51.9 |
| 6.5 | M | 52.5 | 12 | 16.9 | 53.1 |
| 7 | N | 54 | 13 | 17.3 | 54.4 |
| 7.5 | O | 55.5 | 14 | 17.7 | 55.7 |
| 8 | P | 57 | 15 | 18.1 | 57.0 |
| 8.5 | Q | 58 | 16 | 18.5 | 58.2 |
| 9 | R | 59.5 | 17 | 18.9 | 59.5 |
| 9.5 | S | 60.5 | 18 | 19.4 | 60.8 |
| 10 | T | 62 | 19 | 19.8 | 62.1 |
| 10.5 | U | 63 | 20 | 20.2 | 63.4 |
| 11 | V | 64.5 | 21 | 20.6 | 64.6 |
| 11.5 | W | 65.5 | 22 | 21.0 | 65.9 |
| 12 | X | 67 | 23 | 21.4 | 67.2 |
| 12.5 | Y | 68 | 24 | 21.8 | 68.5 |
| 13 | Z | 69.5 | 25 | 22.2 | 69.7 |
Three ways to measure your ring size
- String or paper strip: wrap around the base of your finger, mark the overlap, measure the length in mm.
- Existing ring: measure the inside diameter of a ring that fits and match it to the chart.
- Printable sizer: print at 100% scale and slide it on until it fits over the knuckle snugly.
Average ring sizes
| Group | Common US size | Circumference (mm) |
|---|---|---|
| Women | 6 to 7 | 51.9 to 54.4 |
| Men | 9 to 11 | 59.5 to 64.6 |
Tips for accurate measuring
Measure three times on different days, avoid cold hands, and choose the size that slides over the knuckle with slight resistance. Use the ring size calculator for instant conversion.
Frequently asked questions
What size is a 54.4 mm circumference ring?
A circumference of 54.4 mm is a US size 7, UK N, EU 54 and Japan 13.
What is the average women's ring size?
Most women wear a US size 6 to 7, about 51.9 to 54.4 mm in circumference.
What is the average men's ring size?
Most men wear a US size 9 to 11, about 59.5 to 64.6 mm in circumference.
Should I size up for a wide band?
Yes. Wide bands fit tighter, so many jewelers recommend going up a quarter to a half size for bands over 6 mm.