US to Japan ring size converter
Japanese ring sizes follow the JIS standard, a numeric scale based on inner diameter in roughly 1/3 mm steps. The numbers do not line up with EU numbers even though both are numeric. A US 6 is about a Japan 11, and a US 7 is about a Japan 14. Convert your size below.
Quick answer
A US 7 is 14 in Japan (about 54.4 mm inner circumference). Use the converter for your exact size, or the chart below for the full range.
Between two sizes? Size up for a comfortable fit, see how to measure accurately.
US → Japan at a glance
- 4 = 7
- 5 = 9
- 6 = 11
- 7 = 14
- 8 = 16
- 9 = 19
- 10 = 21
- 11 = 24
US to Japan ring size chart
| USUS / Canada | JPJapan | mmCircumference | mmDiameter |
|---|---|---|---|
| 4 | 7 | 46.7 | 14.9 |
| 4½ | 8 | 48.0 | 15.3 |
| 5 | 9 | 49.3 | 15.7 |
| 5½ | 10 | 50.5 | 16.1 |
| 6 | 11 | 51.8 | 16.5 |
| 6½ | 13 | 53.1 | 16.9 |
| 7 | 14 | 54.4 | 17.3 |
| 7½ | 15 | 55.6 | 17.7 |
| 8 | 16 | 56.9 | 18.1 |
| 8½ | 18 | 58.2 | 18.5 |
| 9 | 19 | 59.5 | 18.9 |
| 9½ | 20 | 60.7 | 19.3 |
| 10 | 21 | 62.0 | 19.7 |
| 10½ | 22 | 63.3 | 20.1 |
| 11 | 24 | 64.6 | 20.5 |
| 11½ | 25 | 65.8 | 21.0 |
| 12 | 26 | 67.1 | 21.4 |
Common questions
How do I convert a US ring size to Japan?
Enter your US size in the converter above and read the Japan result, or find your row in the chart below. Every value is calculated from the ring’s inner circumference, so it works in both directions.
What is a US 7 in Japan?
A US 7 is 14 in Japan. That ring has an inner circumference of about 54.4 mm.
Related conversions
Or see the full ring size chart.