The correct size will be the ring that is the smallest you can comfortably get on and off. Wider rings have more surface and therefore more friction and will need to be slightly larger for a comfortable fit. We do have a sizing strip that we can send you, or you can either try on rings of known size or go to a jeweler and get your size from his/her finger gauge. American and Canadian number sizes are given in our literature. We can convert to other scales, millimeter or decimals of an inch measurements. Ireland, U. K., Australia and some other countries use a letter scale that we can convert to as well. Click Here for Ring Size Conversion Chart Give us your size in any of these measurements and we can give you the right size.