Ring size, without asking

A ring is a lovely surprise until it doesn't fit. Here's how to get close without giving it away, and what to do if you're off.

Find a size without asking

Borrow a ring they wear on the same finger and have a jeweler measure it. If you can't take it away, press it into a bar of soap or trace the inside on paper, and bring that instead. Tell the jeweler which hand it's worn on. GIA says the ring finger on the dominant hand is usually about half a size larger.

A friend or family member may already know. Skip string or a strip of paper around the finger: GIA notes that string stretches, paper curls, and neither accounts for the knuckle.

If you're not sure

Go a little larger. GIA notes it's easier to remove metal from a ring that's too big than to add metal to one that's too small. Fingers also change with heat, cold, and time of day, so one reading is a close guess, not a final answer.

Resizing

Some rings are hard to resize. GIA names pavé and channel settings, and bands set with stones all the way around. For steel, ceramic, or a ring with electronics inside, ask the store how sizing and exchanges work before you buy.

Smart rings size differently

Oura says its rings come in whole sizes only and differ slightly from standard US sizes, so it asks you not to size from other rings. It suggests wearing its plastic sizer for at least 24 hours, and choosing the smaller size if you're between two. Other smart ring makers have their own charts, so check the maker's sizing page.

Sources: GIA 4Cs, How to Determine Ring Size: Tips and Ring Size Chart; Oura Member Care, How to Choose the Right Oura Ring Size. Both read October 19, 2026.

Giving an NFC ring? Read how NFC jewelry works. For an anniversary, see anniversary gifts or Anniversary, from this shelf.