Oura Ring 4 Arrives With A Slimmer Redesign And Upgraded Health Sensors

Oura, one of the leading makers of smart rings, just announced its Oura Ring 4—it's a slimmer, more accurate wearable thanks to a new algorithm, it has a revamped app, and is available in more sizes compared to the previous model. These changes also bring a $50 price bump over the previous generation finger accessory, and while users can use the ring and view select metrics without a subscription, certain important information are locked behind a $6 month or $70 annual fee.

Some of its biggest improvements are centered around a slimmer and stronger cross section, battery life, and improved accuracy thanks to the redesigned app. Overall smart ring sales have shown that women (mostly in their 20s) are now the largest user group, which is why the Ring 4 also has more ring sizes to choose from, ranging from size 4 to 15. Sorry, still no halfsies. 

To increase long-term comfort, Oura has done two things: firstly, it recessed the sensors that used to protrude from the inner surface into the ring itself, and secondly, it made the ring completely round. Despite moving the sensors further away from the finger, Oura assures that accuracy is even better now: "The sensors are placed asymmetrically within Oura Ring 4, providing a variety of distances and tissue penetration depths for measurements." Doing so apparently helps the ring measure what it needs regardless of differences in people's finger vasculature.

Compared to the Ring 3, the company claims marked data improvements pretty much across the board. Signal quality for blood oxygen sensing (SpO2) has gone up 120%, 15% more accurate breathing disturbance index (BDI), 7% less gaps in daytime HR graphing, and 31% less gaps in nighttime HR graphing, Oura says.


With all of these improvements, Oura somehow has been able to squeeze out an extra day of battery life over the previous model as well. The Ring 4 can plug along for up to eight days before needing a recharge in its revised dedicated dock.

Acceptance of smart rings as alternatives to smartwatches and fitness bands for health and biometric tracking is on the rise, slowly making their way from being merely trends to mainstream. This is in part to greater options on the market like the Samsung Galaxy Ring, Ultrahuman Ring Air, and RingConn Smart Ring, but the biggest factor is probably maturity of the technology itself (plus the fact that some people would rather not wear a smartwatch).

The Oura Ring 4 is available now starting at $349 (FSA/HSA eligible), which is a whole Grant than before, along with six finishes—Silver, Black, Brushed Silver, Stealth, Gold, and Rose Gold. The Oura membership subscription is optional, but for those who want to access information like heart rate variability (HRV) and body temperature, opting in will set them back $70 per year.