Size guide
Find the right fit
A smart ring is not a normal ring. The sensors read through the base of the finger, so the fit decides whether you get usable data at all.
How to measure correctly
- 1Measure the exact finger on the exact hand you will wear it on. A US 8 on the left ring finger is not a US 8 on the right index finger.
- 2Measure at the base of the finger, not the middle. The band sits low, above the knuckle.
- 3Measure at the end of the day. Fingers swell; a fit that works in the morning can be tight by evening.
- 4It should feel secure, not painful. If it spins freely it is too loose. If it leaves a deep mark after an hour, it is too tight.
- 5When in doubt, wear the sizer for 24 hours before you decide — including a night's sleep.
The $6.99 that saves a return
The sizer kit contains every size in the range — $6.99 on its own, free when you order it with a ring. It is the only reliable way to get this right.
Conversion table
| Size | Inner diameter | Circumference | Weight |
|---|---|---|---|
| US 6 | 16.5 mm | 51.8 mm | 3.6 g |
| US 7 | 17.3 mm | 54.3 mm | 3.6 g |
| US 8 | 18.1 mm | 56.9 mm | 3.6 g |
| US 9 | 18.9 mm | 59.4 mm | 3.6 g |
| US 10 | 19.8 mm | 62.2 mm | 3.6 g |
| US 11 | 20.6 mm | 64.7 mm | 3.6 g |
| US 12 | 21.4 mm | 67.2 mm | 3.6 g |
| US 13 | 22.2 mm | 69.7 mm | 3.6 g |
All OSAWALLA rings ship in US sizes 6–13. Sizer kits cover US 6–14 so you can confirm a neighbouring size if you are between two.
- Free US shippingOn orders over $50
- 30-day returnsUnused and resalable
- 12-month warrantyAgainst manufacturing defects
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