Since ring size is affected by the weather, time of day, weight, diet and many other factors, the most reliable method for sizing a ring is to wear it for several months under a variety of conditions. A ring which has been worn for some time can be the most accurate guide, but there are also other methods to determining the appropriate ring size.
It is also important that the ring not only fit the finger, but is also able to be pushed over the knuckle. This means that knuckles must be taken into consideration when getting a woman's ring size.
The most simple solution is to ask her, many women know their ring size.
The average woman's ring size is 6.
If your knuckle is a lot larger than the base of your finger, measure both the base and the knuckle with a strip of 1/2-inch paper and select a size in between the two. When buying larger bands, you may want to consider a ring one size larger, for comforts sake.
Rings sized between 5-7 do not incur an additional charge. Rings sized below 5 or above 7 may incur an additional surcharge depending on additional materials and labor.
Remember to measure your finger in warm temperatures at the end of the day. This is when the most blood will be in your hands, and you will be guaranteed a ring fit that will be comfortable for a lifetime.
| Ring Size (USA) | Measured Size (mm) |
|---|---|
| 3 | 44.1 |
| 3.5 | 45.4 |
| 4 | 46.7 |
| 4.5 | 48.0 |
| 5 | 49.2 |
| 5.5 | 50.5 |
| 6 | 51.8 |
| 6.5 | 53.5 |
| 7 | 54.3 |
| 7.5 | 55.6 |
| 8 | 56.9 |
| 8.5 | 58.2 |
| 9 | 59.4 |
| 9.5 | 60.7 |
| 10 | 62.0 |
| 10.5 | 63.3 |
| 11 | 64.5 |
| 11.5 | 65.8 |
| 12 | 67.1 |
| 12.5 | 68.3 |
| 13 | 69.6 |