The best sleep trackers you can buy: Expert tested

Smart rings are better than smartwatches when it comes to sleep tracking, period. They are easier to wear, less obstructive as you toss and turn in your bed, have longer battery life, and are screenless. All these factors make for a light, inobtrusive wearable that will easily track your sleep. 

This Horizon ring from Oura is a competitive sleep tracker, with insights into everything from sleep efficiency, restfulness, readiness, latency, and more. I've been using the Oura Ring for a while now, and it's not only given me deeper insight into my sleep but supplements those data points with explanations behind the numbers. Oura claims to accurately track sleep cycles, total sleep time, resting heart rate, heart rate variability, and movement. 

Every morning I get a sleep score for last night's sleep and view my heart rate, my sleep efficiency, and my suggested bedtime range for the day. The sleep score helps me understand my energy levels for the day and my activity bandwidth, like whether I should exercise or rest.  The lightweight build of the ring makes it a perfect bedtime companion -- I barely notice it on my finger as I fall asleep, and I eagerly wake up every morning to check my sleep data and get my score. But it's not just deep sleep it can track and point out; the Oura Ring can detect the shortest of naps as well and factor those into your sleep score for the day. Plus, the sleep tab on the app offers up information on sleep efficiency, restfulness, REM, deep sleep, latency, and timing, so you can dig deep and go beyond viewing only a sleep score and your time spent in bed. 

As if there aren't enough sleep-friendly features through the Oura Ring, Oura also unveiled a body clock feature that teaches you more about your circadian rhythms and body clock. The feature measures my sleep chronotype, calculated by my body temperature, sleep-wake cycle, and physical activity, and through this data gathered that I'm most productive during the late morning. 

Also: The best smart rings

The battery life is masterful. It charges quickly and stays charged for days on end. The one downside to the ring is the extra $72 you spend on the Oura subscription a year, on top of the $350 you just spent on the ring itself. 

Best Buy reviewers say the ring has helped them improve and further understand their sleep, and they appreciate the lighter build of the ring compared to smartwatches like the Apple Watch. Redditors also agree that the Oura Ring, as a sleep tracker, is worth it. "If you struggle with sleep quality, overtraining, or anything else that affects recovery, I'd say it's worth it," one user wrote in a thread on the topic. One Best Buy reviewer noted, however, that the ring doesn't offer half sizes, which could be an issue if your fingers swell, because the ring won't accurately measure your biometric data, so keep that in mind as you shop for a sleep tracker. 

Oura Ring Gen 3 Horizon specs: Up to 7 days battery life | Sleep cycles | Bluetooth | 7.9mm wide, 2.55mm thick | Up to 100m water resistant | Blood oxygen, skin temperature sensor, heart rate monitoring | iOS and Android compatible

There's no denying the Apple Watch's supremacy in the wearable space, and the Apple Watch Series 9 proves no different. When Apple upgraded its Apple Watch last year, it embedded a new and improved S9 chip to the device and improved its health sensors to make them as accurate and sensitive as possible, ZDNET editor-in-chief Jason Hiner writes in his review. "The more sensitive and accurate health tracking sensors make previous Apple Watches feel outdated by comparison," he says. 

Apple extended the battery life of this watch as well, so you can easily wear this watch to bed without a worry of it dying on you in the middle of the night. Hiner recommends, however, to still plop it on its charger at the end of the day for half an hour before wearing it to bed, just in case. Many users on Reddit also were surprised by the strong battery the watch holds, and how it can last throughout the night and still offer an ample battery in the morning. 

Review: Apple Watch Series 9 

With the Sleep app on Apple Watch, you can create goals for how long you'd like to sleep each night and adjust them for weekdays and weekends, use the Sleep Focus mode, which limits distractions before bed, and track your sleep through the motion detectors on the watch. It estimates how long you spend in each sleep phase, REM, core, and deep, a night. Note that Sleep Focus needs to be on to begin tracking your bedtime activity. 

While Hiner recommends the Apple Watch, he said that the best sleep tracking app on the Apple Watch is not the Sleep app itself, but rather the SleepWatch app. "It includes more data on 'why' you may have slept the way you did: HRV (stress), sleep regularity, sleep disruption, heart rate dip, blood oxygen so that you can potentially change habits or seek medical assistance if sleep patterns aren't going so well," Hiner tells me. 

Apple Watch Series 9 specs: Up to 18-hour battery life | Sleep cycles | Wi-Fi, Bluetooth, GPS, and/or cellular options | 41mm and 45mm models | IP6X dust and water resistant | Blood oxygen, body temperature sensor, EKG, irregular heart rate alerts | iOS only

Android owners looking for a sleep tracker on a smartwatch should look no further than the Google Pixel Watch 2. Google improved its heart rate sensors in its newest iteration of the Pixel Watch, which ZDNET contributing writer and resident smart watch expert Matt Miller confirmed when he tested out the watch himself. 

On top of that, the Google Pixel Watch 2 further integrates Fitbit into the wearable with improved stress tracking, a daily readiness score, ECG, sleep scores, and six months of Fitbit Premium for free. Some of Fitbit's sleep tracking features include nightly trends and trends over time, a silent alarm that vibrates to wake you up during your most optimal sleep stage, bedtime reminders, sleep goals, and more. One Best Buy reviewer said that the watch's silent alarm makes it easy to wake up without waking her husband, and a handful of reviewers pointed out the watch's accurate sleep tracking.  

If you're wearing a piece of tech to bed, it needs to be lightweight and compact. The Pixel Watch 2 is much lighter than its predecessor, ideal for comfortable sleep. "Google's continued focus on sleep and stress tracking means having a lighter, smaller watch makes more sense," Miller writes in his review. 

More: Google Pixel Watch 2 Review 

While the 24-hour battery life isn't nearly as competitive as other smart watches, the faster charging rate takes your 0% battery to 50% in less than 30 minutes. Miller says it's still one of the most accurate Fitbit-powered wearables for heart rate and GPS tracking, so what you lack in battery life you gain in sublime accuracy. 

Google Pixel Watch 2 specs: 24 hours battery life | Sleep stages | 41mm | Up to 164 feet of water resistance | Accelerometer, Altimeter, Compass, Multi-path Optical Heart Rate, Blood Oxygen Sensor, Skin Temperature, Barometer, cEDA, Gyroscope, Light Sensor | Android compatible 

If you're an athlete or fitness junkie shopping around for a new smart watch, you've probably heard about Garmin's smart watches and their suite of health tracking features, like the body battery, workout benefit and recovery time, and perceived exertion data. Most runners I know use one of Garmin's watches for their half marathon and marathon training, and our resident smart watch expert, Matt Miller, loves them for their rugged build. So if you're all-in on your workout regimen, a Garmin watch that's already giving you accurate sport insights that pairs with special sleep capabilities might be your sleep tracker of choice. 

Out of all the Garmin watches, the Venu 3S might be the brand's best for sleep tracking due to its lighter and smaller build and its sleep coach feature, which provides you with a sleep score, tracks your sleep stages and naps, and monitors your heart rate variability and skin temperature during rest. All this sleep tracking data impacts your body battery, which Garmin delivers to you in a score out of 100. 

The sleep coach combines your age, daily and longer-term activity levels, recent sleep history, naps taken, and heart rate variability (HRV) to offer you a recommended nightly sleep need. 

The Venu 3S is of a smaller build than other Garmin watches, which works wonderfully for sleep. The smooth silicone band of the watch also resembles that of the Apple Sport band, according to Miller. Miller's daughter, an avid hiker and napper, tried it out and enjoyed the nap tracking feature on the watch. 

The only downside of this sleep tracker is how it significantly drains the watch's battery, some Amazon reviewers have complained. But even if the battery is drained, its long battery life still out competes many sleep trackers on this list, and is great for anybody who wants to improve their fitness quality through sleep tracking. 

More: This Garmin smartwatch convinced my daughter to switch over from Fitbit 

Garmin Venu 3S specs: Up to 10 days battery life | Sleep score and insights | Bluetooth | 41mm or 45mm | 5 ATM water resistant | GPS, heart rate, pulse oximeter blood oxygen monitor, barometric altimeter, accelerometer | iOS and Android compatible

If you want a lightweight, screen-less band that effortlessly tracks all your activity and sleep data, your best bet could be the Whoop 4.0. Countless professional athletes have used the smart band, given its focus on measuring strain and recovery. But where it really shines is in its sleep tracking. 

Whoop measures your four sleep stages (slow wave, awake, REM, and light) and suggests optimal sleep times based on the sleep data it collects. You can also set alarms that go off at a specific time, once you hit your sleep goal, or once you've hit a recovery period. One of the best sleep features Matt Miller, who reviewed the Whoop 4.0 pointed out, was the sleep coach that not only informs you when to go to bed but tells you how much sleep you will reach if you go to bed past that time. Plus, the Whoop calculates how much sleep you'll need based on the energy you exert on physical or mental tasks. 

You get all your health data through the Whoop smartphone app, given the fact that this band is screen-less. Launching the app displays data on strain, recovery, and sleep. To go deeper into your sleep data, you can get a by-the-minute plot of your heart rate and other sleep metrics during the night, along with some words that describe the data presented for added clarity. 

You can analyze your daily, weekly, and monthly sleep patterns through the detailed sleep trends Whoop offers and calculate your true sleep need, the amount of time you should be sleeping a night. "At first, I thought the Whoop was just an advanced sleep-tracking device that offered more than my GPS sports watches, but it's more than that. It does track the details of your sleep but is also measuring other key metrics of your body throughout the day," Matt Miller writes in his review of the Whoop 4.0. 

Customers agree and say the Whoop is worth the money. Many Amazon reviewers said they initially bought the Whoop 4.0 to track their sleep but found themselves improving other areas of their life thanks to the detailed data and health metrics that Whoop offers. 

Review: Whoop 4.0 

Whoop 4.0 specs: Up to 5 days battery life | Sleep cycles | Bluetooth | 1.5 x 1.5 x 0.45 inches | IP68 water resistant | Blood oxygen, skin temperature sensor, heart rate | iOS and Android compatible