Knuckle Ring Sizer

A ring has to pass over your knuckle to reach the base of the finger. If the gap between your knuckle and base is large, a ring sized for the base won't go on, and one sized for the knuckle will spin around. Most ring size tools ignore this entirely — this one addresses it directly.

Cut a thin strip of paper or use a piece of string. Wrap it snugly around the base of the finger (where a ring normally rests) and mark where it overlaps. Measure that length in millimeters — that's your base circumference. Repeat at the widest point of the knuckle (bend the finger slightly to find it). Measure at the end of the day when fingers are at their largest for the most reliable fit.

A hinged shank (also called an articulated shank) has a small hinge mechanism built into the band. You squeeze the sides to open the hinge, slide it over the knuckle, and release — the ring closes and seats comfortably at the base. They're made specifically for people with a large knuckle-to-base difference and are available from many jewelers on request.

Sizing beads are two small metal balls soldered to the inside of a ring band by a jeweler. They reduce the effective inner diameter slightly so the ring sits higher on the finger and spins less. They're inexpensive, invisible from the outside, and ideal for small-to-medium knuckle gaps.

A spring shank is a ring band with an open back — a small gap in the band that lets it flex slightly when you put it on or take it off. The gap closes once on the finger, giving a snug fit at the base while still passing over a larger knuckle. It's a good middle-ground solution for medium gaps.

Most plain bands and solitaires can be retrofitted with a hinged shank by a skilled jeweler. Eternity bands and rings with stones set all the way around are much harder or impossible to modify, so it's important to choose a compatible style before ordering.