Oura Smart Ring 4 Sizing Kit | Non-Standard Fit - Size Before You Buy - Measure For Best Comfort and Accuracy - Receive Credi
Product details checked 5 September 2026 · price checked live
Check price on Amazon →Overview
OURA Smart Ring 4 Sizing Kit | Non-Standard is one of the 43 wearable technology products in our catalogue, tracked on rating, review volume and live price. The maker describes it as follows: The Oura Ring 4 Sizing Kit helps you find the right size before purchasing. The custom sizer can be used by you or shared with others to determine a comfortable fit. Use the Oura Ring 4 Sizing Kit to find your best fit before purchasing an Oura Ring 4. The sizing kit is non-returnable. Terms and conditions apply. Those are the seller's own claims rather than our testing, so treat them as a starting point. On Amazon it holds 4.6 out of 5 from 1,447 ratings. What that score is worth next to its rivals is set out below.
- Brand
- OURA
- Amazon rating
- 4.6 / 5 from 1,447 ratings
- vs Wearable Technology
- 0.2 above the category median of 4.4
- Rank in category
- 4 of 43 rated wearable technology we track
- Price position
- Mid-priced (category spans £3.99 to £319)
- How proven
- Moderate review volume
Price range as of · details
How it compares in Wearable Technology
Across the 43 rated wearable technology products we track, the typical score is 4.4 out of 5. This one sits at 4.6, which puts it in the upper quarter of the category rather than level with it. Where almost everything is rated well, the gap at the top is small in points and large in practice. That places it 4th of the 43 we rank here.
It carries 1,447 ratings against a category median of 3,467. That is enough of a base to take the score seriously without treating it as settled.
On price it sits in the middle third of a category running from £3.99 to £319, where the midpoint is about £7.99. That is the part of the range where most sensible buys sit, neither cutting corners nor paying for the name.
Category prices as of · details
Worked out from the 43 wearable technology products in our catalogue, not from the brand's own claims. How we rank →
Key features, as the manufacturer lists them
Taken from the product listing via Amazon's product API. These are the seller's claims, not our test results.
- OURA RING 4 SIZING KIT - The Oura Ring 4 Sizing Kit helps you find the right size before purchasing. The custom sizer can be used by you or shared with others to determine a comfortable fit
- SIZING KIT: Use the Oura Ring 4 Sizing Kit to find your best fit before purchasing an Oura Ring 4. The sizing kit is non-returnable. Terms and conditions apply.
- ACCURACY - SMART SENSING - Oura tracks over 30 biometrics, including sleep, activity, stress, heart health, and women’s health metrics. Oura Ring 4 is powered by Smart Sensing, which adapts to you — delivering accurate, continuous data, day and night
- COMFORT AND ACCURACY - A properly fitting Oura Ring will result in the highest data accuracy, comfort, and overall experience
- CHOOSE A FINGER - Oura Ring 4 works on all fingers and can be worn on either hand. For optimal accuracy, we recommend wearing your Oura Ring 4 on your index, middle, or ring finger. Size the exact finger you plan to wear your Oura Ring 4 on
