Measure the inner diameter of an existing well-fitting ring in millimeters:
| Indian Size |
Diameter (mm) |
Circumference (mm) |
| 6 | 14.6 mm | 45.9 mm |
| 7 | 15.0 mm | 47.0 mm |
| 8 | 15.3 mm | 48.0 mm |
| 9 | 15.6 mm | 49.0 mm |
| 10 | 15.9 mm | 50.0 mm |
| 12 (Standard) | 16.5 mm | 51.9 mm |
| 14 | 17.2 mm | 54.0 mm |
| 16 | 17.8 mm | 56.0 mm |
| 18 | 18.5 mm | 58.1 mm |
| 20 | 19.1 mm | 60.0 mm |
| 22 | 19.7 mm | 62.0 mm |
