Ring Size Converter
Convert ring sizes between US, EU, UK, KR, JP & mm
Ring Size Chart
| US | EU | UK | KR | JP | Dia. | Circ. |
|---|---|---|---|---|---|---|
| 3 | 44 | F | 3 | 4 | 14.1mm | 44.2mm |
| 3.5 | 45 | G | 4 | 5 | 14.3mm | 44.8mm |
| 4 | 46.5 | H | 5 | 7 | 14.9mm | 46.8mm |
| 4.5 | 47.5 | I½ | 6 | 8 | 15.3mm | 47.8mm |
| 5 | 49 | J½ | 8 | 9 | 15.7mm | 49.3mm |
| 5.5 | 50 | K½ | 9 | 10 | 16.1mm | 50.3mm |
| 6 | 52 | L½ | 12 | 12 | 16.5mm | 51.8mm |
| 6.5 | 53 | M½ | 13 | 13 | 16.9mm | 53.1mm |
| 7 | 54 | N½ | 14 | 14 | 17.3mm | 54.4mm |
| 7.5 | 55.5 | O½ | 15 | 15 | 17.7mm | 55.7mm |
| 8 | 57 | P½ | 16 | 16 | 18.1mm | 56.9mm |
| 8.5 | 58 | Q½ | 17 | 17 | 18.5mm | 58.2mm |
| 9 | 59 | R½ | 18 | 18 | 18.9mm | 59.5mm |
| 9.5 | 60.5 | S½ | 19 | 19 | 19.4mm | 60.8mm |
| 10 | 62 | T½ | 20 | 20 | 19.8mm | 62.1mm |
| 10.5 | 63 | U½ | 21 | 22 | 20.2mm | 63.4mm |
| 11 | 64 | V½ | 22 | 23 | 20.6mm | 64.6mm |
| 11.5 | 65.5 | W½ | 23 | 24 | 21mm | 65.9mm |
| 12 | 66.5 | X½ | 24 | 25 | 21.4mm | 67.2mm |
| 13 | 69 | Z+1 | 26 | 27 | 22.2mm | 69.7mm |
Diameter / Circumference Converter
Formula: Circumference = Diameter x π (3.14159)
How to Measure Ring Size
String Method
- Wrap a piece of string or dental floss around your finger.
- Mark where the ends meet.
- Measure the length in millimeters -- this is the circumference.
- Find your size in the chart above.
Paper Strip Method
- Cut a thin strip of paper (about 10mm wide).
- Wrap it snugly around your finger.
- Mark the overlap point with a pen.
- Measure the strip with a ruler in mm.
Existing Ring Measurement
- Place a well-fitting ring on a flat surface.
- Measure the inner diameter with a ruler in mm.
- Use the diameter-to-size chart above.
Tip: Measure your finger at the end of the day when it is slightly larger. If between two sizes, choose the larger one for comfort.
◈ How to Use
1
Select your ring size system (US, EU, UK, KR, JP, or diameter/circumference)
2
Enter or select your ring size
3
View your ring size in all international systems
◉ Who Is This For?
- ✓Couples shopping for engagement or wedding rings internationally
- ✓Online jewelry shoppers converting between size systems
- ✓Jewelers working with international customers
★ Why Choose EllyTools?
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