Both RingConn and Oura ship free sizing kits before your real ring — the difference is in the range and precision. RingConn covers whole sizes 6 through 14, with no half sizes, while Oura offers half sizes across a wider overall range. RingConn also tends to run thinner and lighter, which matters if you’re sizing a smaller finger and worried about bulk.
Neither brand recommends trusting your everyday ring size. Both build sizing kits specifically because their internal sensor housings change how a given size number actually feels — but the details of how each kit works, and what range it covers, differ enough to matter.
Quick Comparison
| RingConn Gen 2 | Oura Ring | |
| Size range | US 6–14, whole sizes only | Ring 5: US 6–13 · Ring 4: US 4–15, both with half sizes |
| Half sizes | Not available | Available |
| Sizing kit | Free, 9 sample sizes | Free, shipped before the real ring |
| Recommended trial | 24+ hours on index, middle, or ring finger | Several days, including overnight |
| Build | Thinner, lighter — often preferred for small fingers | Slightly thicker; wider finish selection |
| Subscription | None required | Effectively required for most detailed metrics |
Why RingConn’s Size Range Is Narrower
RingConn Gen 2’s sizing kit includes nine sample sizes, covering US 6 through 14 in whole numbers only, no half sizes. Samsung’s Galaxy Ring follows a similar whole-size-only pattern, which we cover in more detail in our
Galaxy Ring comparison. If your true size lands between two whole numbers — say, 8.5 — you’ll need to choose the closer of size 8 or 9, since RingConn has no half-size option to split the difference.
Why RingConn Often Feels More Comfortable on Smaller Fingers
Multiple hands-on comparisons note that RingConn’s build is noticeably thinner and lighter than Oura’s, which shows up most on smaller fingers or during sleep — some users who found Oura Ring bulky on a small finger size have switched to RingConn specifically for that reason. If comfort and minimal bulk are your top priority and your size falls within 6–14, that’s a real point in RingConn’s favor.
The tradeoff is range: if your true size falls below 6 or above 14, RingConn isn’t an option at all, while Oura Ring 4’s 4–15 range covers more ground on both ends.
Why Oura’s Half Sizes Can Simplify the Decision
Because Oura offers half sizes, someone landing between two whole numbers has an actual size built for that measurement rather than a compromise. Oura Ring 5 covers US 6 to 13; Oura Ring 4 extends further, from 4 to 15.
You can get a fast first estimate with our ring size calculator, which supports half-size precision, or check the full breakdown on our Oura Ring size chart. If you’d rather measure without ordering a kit first, our printable ring sizer is a free, at-home alternative.
If You’re Switching Between the Two
Don’t assume a RingConn size carries over directly to an Oura size, or vice versa — the two brands use different sizing kits calibrated to different sensor housings and ring thickness. Someone who wears a RingConn size 9 comfortably might land at a different Oura size entirely, especially since Oura’s ring body is thicker. Treat a switch as a fresh sizing decision, and lean on the sizing kit or calculator rather than memory.
Frequently Asked Questions
Does RingConn come in half sizes?
No. RingConn Gen 2 is only available in whole US sizes from 6 to 14. If your true size falls between two whole numbers, you’ll need to choose the closer of the two.
Is RingConn or Oura Ring more comfortable for small fingers?
RingConn is generally thinner and lighter, which several reviewers note makes it more comfortable on smaller finger sizes compared to Oura’s slightly thicker build. If your size is within RingConn’s 6–14 range, it’s worth considering for that reason alone.
Do I need a sizing kit for both rings, or can I use my normal ring size?
Both RingConn and Oura strongly recommend using their respective sizing kits rather than relying on your everyday ring size, since each brand’s internal sensor housing changes how a given size number actually fits.
What if my size is outside RingConn’s range?
RingConn Gen 2 only covers US sizes 6 through 14. If you measure below 6 or above 14, Oura Ring 4 — with its wider 4 to 15 range — may be the better fit by default.
