US 12 to Japan ring size
US ring size 12 is Japan 25 — 21.39 mm inner diameter (67.2 mm circumference).
Your size is US 12 (UK Y, EU 67).
Fit confidence Exact table match
Measurement confidence 70/100 · Medium Standard chart conversion; final fit still depends on band width and knuckle shape. Confirm with a printable or physical sizer before ordering an expensive ring.
- US
- 12
- UK
- Y
- EU / ISO
- 67
- Japan
- 25
- CH / IT / ES
- 27
- Ø mm
- 21.39
- Circ mm
- 67.2
| US | UK | EU | JP | CH | Ø mm | Circ mm |
|---|---|---|---|---|---|---|
| 3 | F½ | 44 | 4 | 4 | 14.07 | 44.2 |
| 3.5 | G½ | 45 | 5 | 5 | 14.48 | 45.5 |
| 4 | H½ | 47 | 7 | 7 | 14.88 | 46.8 |
| 4.5 | I½ | 48 | 8 | 8 | 15.29 | 48.0 |
| 5 | J½ | 49 | 9 | 9 | 15.70 | 49.3 |
| 5.5 | K½ | 51 | 10 | 11 | 16.10 | 50.6 |
| 6 | L½ | 52 | 12 | 12 | 16.51 | 51.9 |
| 6.5 | M½ | 53 | 13 | 13 | 16.92 | 53.1 |
| 7 | N½ | 54 | 14 | 14 | 17.32 | 54.4 |
| 7.5 | O½ | 56 | 15 | 16 | 17.73 | 55.7 |
| 8 | P½ | 57 | 16 | 17 | 18.14 | 57.0 |
| 8.5 | Q½ | 58 | 17 | 18 | 18.54 | 58.3 |
| 9 | R½ | 60 | 18 | 20 | 18.95 | 59.5 |
| 9.5 | S½ | 61 | 19 | 21 | 19.35 | 60.8 |
| 10 | T½ | 62 | 20 | 22 | 19.76 | 62.1 |
| 10.5 | U½ | 63 | 22 | 23 | 20.17 | 63.4 |
| 11 | V½ | 65 | 23 | 25 | 20.57 | 64.6 |
| 11.5 | W½ | 66 | 24 | 26 | 20.98 | 65.9 |
| 12 | Y | 67 | 25 | 27 | 21.39 | 67.2 |
| 12.5 | Z | 68 | 26 | 28 | 21.79 | 68.5 |
| 13 | Z½ | 70 | 27 | 30 | 22.20 | 69.7 |
Nearby sizes
| US | Japan | Ø mm |
|---|---|---|
| 11 | 23 | 20.57 |
| 12 | 25 | 21.39 |
| 13 | 27 | 22.20 |
Frequently asked questions
What is US 12 in Japan ring size?
US ring size 12 is Japan 25 (inner diameter 21.39 mm, circumference 67.2 mm).
Is US 12 the same as Japan 25?
Yes — a US size 12 ring equals Japan 25. They are different scales for the same physical size (21.39 mm inner diameter).
Explore
Ring Size Conversions — All Systems & Sizes · Size 12 · See the full international ring size chart