Review: The New Oura Ring 5 Is Its Slimmest Yet—But That’s Hardly Its Most Impressive Feature

The Oura Ring 5 bills itself as the “world’s smallest smart ring,” 40 percent smaller than the previous model. It offers the full suite of health metrics (more than 50 total) in that compact package, along with a reimagined battery that’s supposed to last 6 to 9 days. (In my experience, with full-time use, it’s about 6 to 7.)

You may know your ring size, but you shouldn’t rely on that when it comes to smart rings. Across the board, I’ve found they run a bit small, but Oura makes it remarkably easy to find your perfect fit. You can snag a free sizing kit directly from the brand or visit a Target store to get one. (It cost $10 at Target, but they automatically gave me a $10 gift card when I ordered it online for curbside pickup.)

Inside the kit are plastic rings in each size, so you can get a sense of exactly how it will feel when you wear it. I recommend wearing it for at least one to two days, so you can see how it feels as your fingers swell throughout the day. I’m so glad I did that—in fine jewelry, I’m an 8.5, but my Oura ring is a size 10.

It’s Dainty Yet Durable

The Oura 5 is as close to a traditional ring as I’ve ever seen. (It’s about as thick as 10 sheets of paper, or a ‘90s thumb ring.) The edges are smooth, and it’s an incredibly comfortable fit, even if I’ve gone overboard on salt and my fingers are sausage-y. If someone shakes my hand, the squeeze doesn’t make me feel like my bones are about to crumple around the ring—a discomfort that’s made me abandon other smart rings and bulky jewelry.

It’s also managed to stay scuff-free in its 45 days of nonstop use. As someone who’s constantly tackling DIY projects, wrangling small children and has been known to break permanent jewelry within just a few weeks of it being soldered to my wrist (twice, actually), that’s impressive.

OK, here’s my biggest issue with most health trackers: You either get raw data you have no idea what to do with (I was in REM Sleep for an hour and 32 minutes? What does that mean, exactly?) or such basic insights that it’s not all that helpful (my stress spiked last night as I fought to convince my toddler that watermelon toothpaste is not food, nor is it fingerpaint? Revolutionary!).

Oura finds that missing middle ground, offering advanced data that’s surprisingly accurate with analysis that helps make sense of the data, offering actionable insights. So, while it tracks how long you slept, breaking it down into REM sleep and deep sleep, it will also share your sleep latency (aka how long it took you to conk out) and log your resting heart rate and breathing patterns. Each data point includes an explanation of what that means for you. Over time, it will start to learn your preferred sleep pattern, known as your sleep chronotype, and offer suggestions to help you live in alignment with that pattern, so you can wake up feeling less groggy and more alert overall.

Sleep isn’t the only thing it tracks; it’s also got a great gauge for activity. (I don’t need to tell it I’m exercising, like I’ve had to do with Fitbits and smart watches; it detects it and usually knows exactly what I’m doing, be it a jog, brisk walk or Pilates.)

The heart and stress monitoring functions have interested me the most. My sister has a rare heart condition that could be hereditary, and my cardiologist has asked me to watch out for abnormalities in my heart rate. Oura makes that easy, and while learning that my cardiovascular age is 1.5 years older than my actual age was disappointing, it also inspired me to bump up my overall activity (another flag it noticed—apparently spending all day hunched over a laptop isn’t great for you).

The stress monitoring has also been interesting. Rather than alarm me, it’ll let me know about normal or healthy increases in stress throughout the day, and if things get too high, it’ll offer a short Headspace exercise to help me unwind.

While my smartwatch can monitor my sleep, I never wear it to bed because it needs that time to charge. Similarly, I’ve found I’ve abandoned other trackers early, simply because I hate having to charge them every other day or so. With Oura 5 lasting a full week—and charging rapidly, in just a couple hours—it’s easy to charge after dinner and slip back on before bed.

The One Thing I’d Change

The cheapo in me would nix the monthly subscription cost—that was a big deterrent early on—but right now, I’ve been enjoying learning about myself and seeing how small changes in my bedtime routine, diet and exercise improve my scores (and make me feel). And I see how Oura constantly builds on its tech and improves it, offering fresh insights and deeper analysis the longer you use the device, so the cost makes sense. Without a subscription, you simply receive three daily scores—readiness, sleep and activity—and basic status alerts, like battery level. That makes it hardly worth the initial cost, unless you really like it as a piece of statement jewelry.

The Oura Ring 5 is truly impressive, and that level of technology and insights comes at a cost. If you’re trying to improve your health and want to stay more informed about what’s going on with your body, it’s a great option. (My father, for example, is recovering from heart surgery and was recently diagnosed with diabetes, so I’m seriously considering an Oura Ring 5 with Stelo glucose monitoring integration for him.) I may not be a biohacker, but I do feel like I’m making better decisions with my health, even if they’re micro changes, each day, as a result of wearing this little ring. And to me, that’s huge.

Fast Facts

• HSA/FSA Eligible? Yes
• Tracks: sleep quality (Deep sleep, REM and light sleep stages; total sleep time, nighttime movement, etc.), heart rate, heart rate variability (HRV), cardio capacity (VO2 max), activity (steps, distance/movement goals, etc.), stress levels, body resilience, menstrual cycles, period predictions, fertility windows
• Sizes: 6-13