Method one: measure an existing ring
- Choose a ring that fits the intended finger at the position where the new ring will sit.
- Measure the inside diameter across the widest point without including the metal edge.
- Compare the millimetre measurement with the table below.
Method two: measure your finger
- Wrap a non-stretch paper strip around the intended finger without pulling it tight.
- Mark where the ends meet and measure that length in millimetres.
- Repeat later in the day and ensure the strip can pass over the knuckle.
Print calibration
Print at 100% or “actual size,” then measure this bar with a physical ruler. If it is not exactly 50 mm, do not use the printed dimensions.
50 mm
| Size | Inside diameter | Finger circumference |
|---|---|---|
| 4 | 14.9 mm | 46.8 mm |
| 4.5 | 15.3 mm | 48.0 mm |
| 5 | 15.7 mm | 49.3 mm |
| 5.5 | 16.1 mm | 50.6 mm |
| 6 | 16.5 mm | 51.9 mm |
| 6.5 | 16.9 mm | 53.1 mm |
| 7 | 17.3 mm | 54.4 mm |
| 7.5 | 17.7 mm | 55.7 mm |
| 8 | 18.1 mm | 57.0 mm |
| 8.5 | 18.5 mm | 58.2 mm |
| 9 | 18.9 mm | 59.5 mm |
| 9.5 | 19.4 mm | 60.8 mm |
| 10 | 19.8 mm | 62.1 mm |
| 10.5 | 20.2 mm | 63.3 mm |
| 11 | 20.6 mm | 64.6 mm |
| 11.5 | 21.0 mm | 65.9 mm |
| 12 | 21.4 mm | 67.2 mm |