Smart ring size advisor
Start from your normal jewelry size, then pick the target smart ring. The advisor gives a conservative first size to test and the sizing-kit step that matters for that brand.
Smart-ring advisor
Smart-ring sizing advisor
Why this is not a final order size
Smart rings fit differently from jewelry because sensors need steady skin contact. Your usual US size can be useful for narrowing the kit sizes, but comfort, swelling, sleep and sensor placement decide the final size.
For Oura Ring 5, do not reuse an old Ring 4 result without re-checking. Oura says Ring 5 sizing
is slightly different from Ring 4 and uses a different published size range.
Frequently asked questions
Can I use my normal ring size for a smart ring?
Use it only as a starting point. The brand sizing kit is the final check.
Should I size up for a smart ring?
Sometimes. Test the brand kit, especially if your jewelry size is a half size.
Does Oura Ring 5 use the same size as Ring 4?
Not automatically. Ring 5 has a redesigned interior and should be re-checked.