I've Tested Many Smart Rings—The Oura Ring 4 Is My Favorite Yet

Oura Ring 4 Design & Build Quality

As a pioneer in the smart ring market, it's expected that Oura will introduce noticeable improvements with each new release. The Oura Ring 4—the latest generation—is no exception, featuring a polished design, additional sizing options, and the removal of internal bumps for improved sensor accuracy.

I tested the Oura Ring 4 in Stealth finish, size 8, which retails for $399—not exactly cheap, especially considering the additional subscription fee of $5.99 per month or $69.99 annually. However, in terms of quality, this is undeniably a premium wearable.

While the Ring 4 doesn't have an official IP rating, it does offer impressive water resistance, capable of handling depths up to 100 meters (approximately 328 feet). This makes it suitable for showering, swimming, and recreational diving like snorkeling.

I've been using the ring for three weeks now, and although I typically remove it during weight lifting sessions or activities involving water—like washing my hands or dishes—it still shows virtually no signs of wear. This durability is noteworthy for a smart ring exposed to diverse daily conditions.

As always with smart rings, it's crucial to ensure the device fits perfectly to avoid issues when your hands become sweaty, cold, or swollen. If you experience finger swelling after workouts, I recommend shifting the ring to another finger—this strategy has worked seamlessly for me.

With a slim profile of approximately 2.88 mm thickness, wearing it on my index finger has been effortless. It doesn't restrict movement, feels incredibly lightweight, and maintains an elegant appearance suitable for any occasion.

Oura includes a subtle mark at the bottom of the ring to help users ensure correct positioning, with the primary sensors placed securely against the bottom of your finger. Honestly, once it's on, the ring feels like any other jewelry you would wear.

Finally, the red, green, and infrared LEDs used for measuring heart rate, heart rate variability (HRV), and blood oxygen are so discreet that I only notice them during nighttime, particularly when reading my Kindle in bed with the lights off.

If you're seeking a seamless addition to your daily routine—something you'll likely forget you're even wearing—a smart ring is ideal. In that regard, the Oura Ring 4 is unquestionably a 5-star device.

Oura Ring 4 Software & Compatibility

The Oura Ring 4 is compatible with both Android and iOS devices and supports over 40 app integrations, including Apple HealthKit and Google Health Connect. However, its language availability is a bit limited. It works with most nextpit domain languages like English, German, French, and Spanish but lacks support for Portuguese.

Oura offers a well-designed companion app that acts as the central hub for all your health data. The app recently underwent a UI simplification—a sort of facelift—making navigation more intuitive. Key health scores now appear at the top of the homepage for a quick overview, and you can customize their display as you prefer. The app features three main tabs that make navigating through your data straightforward.

Oura is also making strides in introducing AI features. Although still in beta, they already offer a promising experience. For example, you can now take pictures of your meals to quickly log nutritional data, and there's a Health Advisor—an AI-driven wellness coach.

As someone who uses the paid version of MyFitnessPal to track macros, I find Oura’s Meal feature still too basic. It categorizes meals' macros into broad labels like low, medium, or high, lacking the detailed breakdowns serious users might want. Although snapping a photo to log a meal is easy, having to stop and manually correct the analysis can be frustrating. Overall, this feature still needs significant refinement to become truly useful.

The AI Health Advisor reminds me of Whoop's AI Coach, which I really like. It uses the data collected by the ring to offer personalized health insights. Over time, interacting with the AI Advisor could genuinely influence how you approach your wellness journey with the Oura Ring 4.

As mentioned before, the Oura app operates under a subscription model, which is required to unlock the device's full potential. Considering the breadth of features offered, I believe the subscription is reasonably priced and, frankly, essential.

Oura Ring 4 Wellness and Health Tech

First, it's important to clarify: the Oura Ring 4 is ideal for those who want to fine-tune their biology to feel, look, or perform better. However, it’s not designed to be a daily step counter or a detailed workout monitor. That said, the smart ring does provide powerful tools to support lifestyle changes—but it lacks features like built-in GPS or the ability to connect to external hardware.

In this sense, Oura positions itself clearly as a wellness-focused wearable. It analyzes sleep, readiness, and recovery to generate insights like stress resilience and cardiovascular age, helping users build a more advanced health plan—whether independently or with the guidance of a professional.

Activity Tracking

While you can use the Oura Ring 4 to track heart rate zones during activities like outdoor cycling, running, or strength training, fitness tracking isn’t its primary strength. Also, to start an activity recording, you’ll need to initiate it through the companion app on your smartphone, which means you must have your phone with you. Unlike other fitness trackers, the Oura Ring doesn't provide real-time feedback, such as vibration alerts for distance milestones during a run.

Oura does support integration with Apple HealthKit, Google Health Connect, and apps like Strava. Impressively, it labels all imported data so you always know which service the information came from—something I wish Samsung would implement with their wearables.

Two points to highlight here:

• Heart Rate Accuracy: While the PPG sensors work fairly well during daily use, I found heart rate tracking during running a bit less reliable. Compared to the Wahoo Tickr chest strap*, the Oura Ring 4 tended to slightly overestimate average heart rate and underestimate peak heart rate. Although the deviations were minor and typical for optical sensors, those needing highly precise data might prefer chest straps or dedicated fitness trackers.
• Step Tracking: Step counting is not a major focus for Oura, and it shows. During testing, step counts were often underreported compared to manual tracking. That’s because Oura treats steps as background data, prioritizing overall activity levels and recovery instead of precise step counts.

Readiness

Using metrics like resting heart rate, HRV, sleep quality, and recovery index, Oura calculates a Readiness Score that reflects your body’s capacity to handle daily stressors, including workouts. A high score suggests you’re ready to perform, while a lower score recommends prioritizing recovery.

I found Oura’s readiness algorithm to be largely accurate, aligning with my physical and emotional state about 85% of the time.

Sleep & Wellness

When it comes to sleep tracking, the Oura Ring 4 truly shines and stands out from competitors. Apart from sleep sheets, a smart ring like this offers one of the most comfortable ways to track sleep without disrupting it. For someone like me who prioritizes sleep, Oura delivers a highly detailed and accurate breakdown of sleep stages. Most nights, its data closely matched my reference device, the Apple Watch Series 9 (review), which is considered one of the best sleep trackers available.

Beyond sleep metrics, I appreciated Oura’s partnership with trusted services to provide meditation guides, breathing exercises, sleep tips, and educational tutorials—helping users not only collect data but also understand it.

For those who menstruate, Oura integrates menstrual cycle tracking into its health insights, factoring in hormonal fluctuations and wrist temperature to estimate fertility windows and predict readiness impacts. This is a thoughtful addition that deepens the device’s health relevance.

My Health Tab

The more data you collect, the more valuable your insights become. After using the Oura Ring 4 for over three weeks, the My Health tab quickly became one of my favorite features. Powered by Oura’s Smart Sense algorithm, it offers personalized guidance on your wellness journey, taking into account your finger’s unique characteristics—such as shape and skin tone—to better calibrate the ring’s sensors.

It was gratifying to see how my efforts to manage daily stress and improve cardiovascular fitness (VO2 Max) were reflected in physiological metrics like cardiovascular age. The My Health section also allows tracking of sleep trends over time.

I'm still waiting to unlock my Body Clock readings, which offer insights into my chronotype and ideal circadian rhythm. This feature takes more time to populate since it requires consistent data collection, but it’s a promising and research-backed addition that’s not commonly available in consumer wearables.

Overall, Oura offers an impressive depth of insight into personal wellness, all while maintaining a strong commitment to health data privacy and consistently evolving through thoughtful software updates. It’s one of the rare wearables that doesn’t just track your health—it feels like a true partner.

Battery Life and Charging

Despite the limited form factor of smart rings, the Oura Ring 4 handles battery life impressively well. In my experience with the size 8 model, I consistently got a solid seven days of battery life. Larger sizes might yield slightly different results. Once the battery drops to 20%, the app starts sending notifications so you're never caught off guard.

With this new generation, Oura has redesigned the charger, and it's a welcome upgrade. Sleek and compact, it looks great on a bedside table or a desk, whether at home or in the office. However, charging from 0 to 100% takes around 80 minutes, which is relatively long.

One area where Oura still lags behind is offering a portable charging case—something Samsung includes with the Galaxy Ring and RingConn with the Smart Ring Gen 2. I'm a big fan of this feature since it allows you to charge the ring on the go multiple times without needing an outlet.

Another downside is that the device relies heavily on the connected smartphone’s processing power to run its algorithms, which can significantly impact your phone’s battery life. In my case, I paired it with an iPhone 16 (review) running iOS 18, and the Oura Ring app accounted for 17% of battery usage over the past 10 days. For comparison, the Whoop app consumed 8%, and Apple Health used 4% during the same period.

That said, the Oura Ring 4 delivers solid battery performance overall. Charging is easy to manage with the included charger, which conveniently uses a USB-C connection.

Oura Ring 4 Key Specs

	Oura Ring 4
Product	Oura Ring 4
Image
Dimensions and Weight	7.90 mm width × 2.88 mm thickness 3.3 to 5.2 g (depending on size)
Colors	Varies by collection (e.g., Silver, Black, Gold, Stealth)
Sizes	US 4 to US 15 (depending on market)
Sensors	Red, green, and infrared LEDs for heart rate, HRV, blood oxygen (SpO₂) Temperature sensor Accelerometer for activity tracking
Connectivity	Bluetooth Low Energy (EMF-safe, airplane mode available)
Certifications	Water resistant up to 100m / 328 ft, FCC-certified
Battery	Up to 8 days of battery life Charges in 20–80 minutes
Software versions	Oura App available on iOS & Android Integrates with 40+ apps Supports English, Finnish, Japanese, German, French, Spanish, Italian, Norwegian, Swedish, Danish

Where to Buy the Oura Ring 4

If you're looking to purchase the Oura Ring 4 in the US, you have several reliable options. The easiest and most comprehensive place to buy is directly through the Oura official website, where you can access the full range of sizes, finishes, and exclusive bundles.

Major retailers like Best Buy and Amazon also carry the Oura Ring 4. Best Buy offers an in-store sizing experience and credits the cost of a sizing kit toward your purchase, while Amazon provides convenience but requires careful attention to buy only from authorized sellers.

Additionally, Target and Costco offer the Oura Ring 4, sometimes bundling sizing kits or extra chargers. Regardless of where you buy, using a sizing kit is highly recommended to ensure a perfect fit. Pricing typically starts at $349, with premium finishes like Stealth and Gold costing more.

Disclaimer: We received the Oura Ring 4 through a campaign with MediaMarkt in Germany. However, rest assured that this partnership does not influence our rating or opinions about the device.