Ring Size Calculator
Find your ring size using finger measurements or convert between US, UK, and EU sizing systems.
Find Size by Measurement
Common Diameters (mm):
Convert Known Size
Your Ring Size
US 7
US
7
UK
N
EU
54
Size Measurements
Inner Diameter
17.3 mm
Circumference
54.4 mm
How to Measure Your Finger
📏
String Method: Wrap a string around your finger, mark where it overlaps, then measure the length in mm.
💍
Existing Ring: Measure the inner diameter of a ring that fits well.
📐
Ring Sizer: Use a printable ring sizer or visit a jeweler for accurate sizing.
💡 Sizing Tips
- • Measure at the end of the day when fingers are largest
- • Avoid measuring when cold (fingers shrink)
- • Measure multiple times for accuracy
- • For wide bands, go up half a size
- • When between sizes, choose the larger size
Ring Size Chart
| US | UK | EU | Diameter (mm) | Circumference (mm) |
|---|---|---|---|---|
| 3 | F | 44 | 14.1 | 44.2 |
| 3.5 | G | 45 | 14.5 | 45.5 |
| 4 | H | 46.5 | 14.9 | 46.8 |
| 4.5 | I | 48 | 15.3 | 48 |
| 5 | J | 49 | 15.7 | 49.3 |
| 5.5 | K | 50.5 | 16.1 | 50.6 |
| 6 | L | 51.5 | 16.5 | 51.8 |
| 6.5 | M | 52.5 | 16.9 | 53.1 |
| 7 | N | 54 | 17.3 | 54.4 |
| 7.5 | O | 55.5 | 17.7 | 55.6 |
| 8 | P | 57 | 18.1 | 56.9 |
| 8.5 | Q | 58 | 18.5 | 58.1 |
| 9 | R | 59 | 18.9 | 59.4 |
| 9.5 | S | 60.5 | 19.4 | 60.9 |
| 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 | 65.5 | 21 | 65.9 |
| 12 | X | 67 | 21.4 | 67.2 |
| 12.5 | Y | 68 | 21.8 | 68.5 |
| 13 | Z | 69.5 | 22.2 | 69.7 |