The best smart rings of 2025: Expert tested and reviewed

At this point in the smart ring race, everyone is trying to beat Oura. But the Oura Ring 4 proves that the smart ring pioneer's position isn't wavering anytime soon. While most smart rings simply provide you with the health data it collects, the Oura Ring 4 tells you the story and the context behind that data for greater information on your health. 

Oura recently revealed the Oura Ring 4, the successor to its popular Oura Ring 3 which debuted in 2021. The new generation comes with smart sensing technology for a more accurate, thinner, less obtrusive, and longer wear with fewer gaps in data capture. Oura upgraded the number of signal pathways (basically how the sensors monitor and collect data inside the ring) from eight in Ring 3 to 18 in Ring 4. It also flattened the inside of the Ring 4 for more comfortable wear (if you have worn the Ring 3, you know how irritating the domed sensors could get around your finger after prolonged wear). Lastly, the smart sensing allows for one extra day of battery life, upgrading from seven days in Ring 3 to eight in Ring 4. 

Oura presents my sleep, activity, and recovery data through a scoring system on the main page. These scores and descriptions enable me to track my progress or pinpoint weak spots over time. The simplified overall score of, say, my readiness or sleep, appears with a detailed chart monitoring heart rate, body temperature, and blood oxygen levels throughout the day and night. 

The ring also senses when I'm stressed and adjusts my daily activity goals accordingly. One recent night, it detected my significantly raised body temperature and suggested I use the rest mode function, which deprioritizes activity and prioritizes rest and recovery. 

Also: Oura Ring 3 vs Oura Ring 4: Which model should you buy? 

There are also eye-opening features like Daytime Stress, which captures your body's stress levels over the day and showcases them on a timeline. Oura allows me to understand my physiological responses to various forms of stress, like a high-intensity workout, a night out with friends, or a bad day. 

What differentiates Oura from its competitors is its amazing user interface that hosts all the health data you could ever need -- while staying mindful not to overwhelm you. Every number or graph is typically followed up with a short and digestible summary that turns your data into a helpful suggestion for sleep, activity, or stress. 

You can also easily click into a metric, whether that's heart rate variability or respiratory rate, and get a historical view of it over time. The ease with which you can look at daily, weekly, and monthly health data -- and how that data is communicated so clearly through the app -- is a major reason why Oura is the best smart ring. 

There are many reasons to opt for Oura, but one that comes up frequently in conversation is how many apps partner with Oura. Natural Cycles, Strava, and other health apps offer data syncing into Oura's app. I love that when I use Strava for runs, it automatically shows up in my Oura timeline. 

Also: The Oura Ring 4 is the best smart ring I've tested so far

This comprehensive but simple approach is evident in the ring's form factor and integrations. The ring syncs with Apple Health, Google Fit, and iOS and Android apps, allowing you to see your daily and even monthly metrics from your mobile device. 

The downside, which Redditors and reviewers often point out, is the $6-per-month membership cost to unlock personal insights, like in-depth morning sleep analysis and temperature trend monitoring (which can even predict early stages of illness). Non-paying members only have access to sleep, readiness, and activity insights. 

Thankfully, Oura's customer service is great. ZDNET staff writer Allison Murray called them after her ring's battery began to falter, and the company sent her another ring free of charge. 

Oura Ring Gen 4 tech specs: Material: Lightweight titanium with non-allergenic, non-metallic inner molding | Battery life: Up to 8 days | Charging: Full charge in 20 to 80 minutes | Compatibility: iOS and Android | Durability: Water-resistant up to 328 feet | Sizing: 4 to 15