Ring 101! Each ring listed has its smallest size beside it, but sterling has about a +1 stretch capability (bigger) UNLESS otherwise indicated. If the ring says 8, you can request it be stretched to a 9 at no additional cost. I am NOT sizing down at this time as that requires torchwork labor. If the ring says adjustable, it either is bypass style or has an open back and the listing will indicate the size range. If you do not know your size but have a fabric tape measure, a millimeter measurement can be converted here.