Of course, the most accurate way to find your size is to have your finger--or a ring that fits---sized by a jeweler. If this is not possible, follow the instructions below.

To determine your ring size, cut a strip of paper 1/2 inch wide by 5 inches long. Wrap the paper around your finger and using a pen, mark where the long end overlaps. Measure the marked length with a ruler, then use the table to determine the closest US size. We recommend that you use the metric side of the ruler for greater accuracy.
Be aware that if you have a large knuckle, you will need to be able to slide the ring past it. Also keep in mind that finger size will be affected by the normal swelling and shrinking caused by hot or cold weather, physical exercise, medication, or weight changes.
If you are ordering a ring with a wider shank, you may want to increase the size slightly. If in doubt, it is always better go slightly larger rather than smaller.

To get someone else’s ring size, you have to be sneaky! You can slip a ring that you know fits well over a taper candle (or your own finger) until the rings stops. For accuracy, mark the candle (or your finger!) above and below the edges of the ring, then measure the area in between as described above.