Oura Ring 4 review: still on top — for now

For the greater part of this past summer, I wore six smart rings at once. I wanted to see which was best, and the Oura Ring Gen 3 was the clear winner. Well, it’s been about two weeks since my experiment ended, and there’s now a new winner: the Oura Ring 4.

Oura has been the top dog in smart rings for the past decade. Sure, there’s been a smart ring renaissance this year, but its rivals are mostly either just getting into the game or launching a second version. This is the fourth Oura Ring. Oura has spent years collaborating with researchers and conducting its own studies. It’s the most readily available at third-party retail stores in the US; it’s the one wellness influencers keep flaunting in TikToks; and it’s seen on the fingers of A-list celebrities. In response to increased competition, Oura has launched half a dozen new features in the past 12 months. And now, Oura is closing out 2024 with several hardware and software refinements.

The Oura Ring 4 extends the company’s lead over the competition. The question is how long Oura can maintain it when its rivals cost less, eschew subscriptions, and have started innovating in new directions.

Slightly better in every way

Wearing the Oura Ring 4 is better than the Gen 3. Just not by much.

The Oura Gen 2 and Gen 3 rings had resin interiors with domed sensor bumps. The fourth-gen ring is made entirely of titanium, and the inside is flatter, with recessed sensors. It might not seem like it, but this is impressive engineering for a device so small. Compared to titanium, the resin in older rings diffused light from the sensors in a less precise way. Since rings naturally rotate during the day, it’s also easy for those sensors to move out of proper alignment. That’s partly why the previous Oura Rings had raised sensor bumps — they ensured good skin contact to mitigate those factors. 

This time around, Oura’s introduced a new Smart Sensing algorithm that increases the number of sensor signal pathways from eight to 18. The sensors are placed asymmetrically to allow for a variety of distances and measurements. Basically, it now matters less if your ring rotates and better accounts for the fact that everyone’s fingers are different. This also means you don’t need those sensor bumps anymore. 

My brain appreciates all the engineering sweat and tears that went into making this possible. Technologically speaking, Oura is flexing on its rivals. But practically speaking, it means close to diddly squat for the average wearer. Ninety-nine percent of the time, wearing the Oura Ring 4 felt the same as the Oura Ring Gen 3 and the Gen 2 before that. The only time I noticed a difference was when I felt bloated. I have knobby knuckles, and the sensor bumps on older Oura Rings could be painful when trying to take the ring off. It was a relief to not have that problem this time around. 

Design-wise, this all-titanium ring is nice but not dramatically different from other premium options like the Samsung Galaxy Ring or the Ultrahuman Ring Air. You’ll notice more of a difference if you’re coming from older Oura models with flat or angled tops. All of the fourth-gen rings are fully round. This isn’t new — Oura introduced fully round versions of the Gen 3 in 2022 — but I’ve found it to be more comfortable. If you are mulling an upgrade, I highly recommend trying the new sizing kit first. I was a size 8 in the old rings, and now I’m a size 9. Plus, Oura’s size range has four new options, spanning sizes 4 to 15. If you were previously a size 6 or 13, you may find one of the newer sizes fits you better.

Another improvement: battery life. You can now get up to seven or eight days on a single charge. I’ve been able to get about 6.5 days, even with the power-guzzling blood oxygen sensing feature enabled. With a Gen 3, I got three to four days. Again, your mileage will vary depending on ring size. (Larger size, larger battery.) This is a significant bump, though I did get longer with the first-gen RingConn and from the Samsung Galaxy Ring when it was paired with a smartwatch. 

Speaking of battery, Oura’s updated the charging dock. It’s larger, metal, and looks sleeker than previous docks. Unfortunately, my hangry cat had no problems knocking it off my nightstand. I wish Oura had opted for a more convenient charging case like many of its rivals, but alas. Maybe next time.

Software and science

Oura’s hardware isn’t that much better than the competition. I maintain the Galaxy Ring’s concave shape is more comfortable, and its charging case more convenient. The Evie Ring’s open-gap design is also fetching and clever for those of us prone to bloating. But where Oura trounces everyone else is software and its commitment to science, both in conducting and communicating it.

Let’s start with software. The app has had a much-needed redesign. Oura released several new features and metrics in the past year, turning the dashboard into a cluttered mess. Now everything’s been streamlined into three tabs: Today, Vitals, and My Health. 

The Today tab contains shortcuts to specific metrics, a timeline of all your daily activity, and cards that highlight different things (e.g., sleep score, readiness, etc) depending on the time of day. Vitals is where you’ll find all your metrics, albeit in a more digestible format. My Health is where you’ll find longer-term health trends and reports. All redesigns take a hot second to adjust to, but overall, I’ve found this to be a helpful reorganization.

Another needed improvement: automatic activity detection has been expanded to 40 activities. (Oura lists roughly 30 of them here.) This makes the ring a much better standalone activity tracker, especially since enabling location permissions will also generate automatic GPS route maps. It’s flexible for smartwatch users, too. I typically don’t track walks on my smartwatch, but Oura picked them up easily. Start and end times, as well as the route maps, were also accurate. Conversely, I much prefer to record my runs and strength sessions with a smartwatch. For those instances, Oura prioritizes manually tracked or imported activities so I didn’t have to worry about duplicate activity records. 

For tracking, Oura cites an external study saying the new Smart Sensing algorithm supports a significant bump in accuracy for signal quality, blood oxygen, and breathing disturbance detection. It also claims users should see fewer occurrences of heart rate data gaps both during the day and at night. 

It’s impossible for a single reviewer to definitively test these claims. The general consensus is that consumer-grade wearable sleep tracking is broadly accurate at the basics but should be taken with a heavy grain of salt. All I can tell you is what I experienced in my own testing. The Oura Ring 4’s sleep and wake times align with my own manual testing logs. I still saw occasional gaps in nighttime heart rate, though it’s hard to say after only two weeks whether there were fewer or greater than before. My heart rate metrics, however, were all on par with my smartwatches — which is a good thing. Step counts and calorie estimates can be inflated compared to smartwatches, but that’s been true of every smart ring I’ve tested. What I can say for Oura, however, is its measurements are consistent and its margin of error is on the smaller side. After years of testing wearables, I trust the Oura Ring’s measurements for sleep and recovery tracking — in fact, I use it as a control for evaluating the sleep tracking features of other devices. 

A big reason for that is this is a heavily studied device. For example, a recently published peer-reviewed study compared the accuracy of its sleep algorithm to the Apple Watch Series 8 and Fitbit Sense 2. Oura’s algorithm was found to be 5 percent more accurate than the Apple Watch and 10 percent more than Fitbit at detecting sleep stages. You should take all studies, including this one, with a healthy dose of skepticism. Not all studies or meta reviews are created equal, and one of the researchers here is a member of Oura’s medical advisory board. That said, Oura has also consistently made an effort to partner with outside researchers to validate its results for years. It also has a record of publishing these weeds-y findings, even if the results are not the most exciting. You see this from big companies like Apple, Samsung, and Google, but it’s much rarer from smaller companies in niche wearable spaces. 

All these things together give Oura the edge among smart rings. The app is polished, I never have to think twice about syncing, the company puts immense effort into continually improving accuracy, and it’s had frequent feature updates in the past year. I’ve no doubt Oura’s competitors will start catching up here. Samsung and Ultrahuman aren’t too far off. But for now, Oura is the one to beat.

The elephant in the room

The weird thing about the Oura Ring 4 is it’s the best smart ring you can get right now. I also think most people don’t need to upgrade.

The hardware experience isn’t drastically different. Oura also won’t gatekeep any of these new software updates or the app redesign to the newest ring. That’s great! But it means there’s little incentive for folks with a Gen 3 to upgrade unless their battery is toast, especially since the starting price has increased to $350, and there doesn’t seem to be a trade-in program. (Current Oura members can get a 10 percent discount, but that’s it.) Really, the Oura Ring 4 is best for new users or people who previously couldn’t find a size that fit them.

For those folks, it’s a matter of whether you can stomach the Oura Ring’s single biggest con: the $6 monthly / $70 annual subscription. I don’t see a point in trying to justify its subscription. You’ll either think everything Oura’s brought to the table is worth it, or you won’t. If you’re the latter, fair enough. My take is that the Oura Ring is worth it if sleep tracking and recovery are your top priorities. Otherwise, a smartwatch is a better investment.

This is and will continue to be Oura’s greatest obstacle. It’s got a substantial lead in this space, but its rivals have made a point of eschewing subscriptions. Samsung, in particular, has large coffers and interesting ideas about how smart rings should interact with other gadgets like phones and smartwatches. For instance, the Galaxy Ring has gesture controls for the Galaxy phone’s camera and gets longer battery life when used with a Galaxy Watch. If Apple comes out with a smart ring, it’ll be a dark day at Oura headquarters. Meanwhile, smaller rivals like RingConn can undercut Oura’s price, even if the tracking is more basic.

Oura is betting that the best is worth paying for. It’s a gambit that will probably hold so long as everyone else is playing catch-up. But ask anyone who races: it’s hard to maintain a lead forever.