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Which sleep monitors are best?

A sleep monitor is a device that tracks a person’s habits and patterns while they sleep. These devices also monitor the quality and duration of a person’s sleep. Anyone can use a sleep monitor, but the people who benefit the most are those who feel like they’re not getting enough rest at night. Sleep monitors may not be able to identify underlying issues like insomnia or sleep apnea, however.

Many sleep monitors also track things like heart rate, oxygen levels and body temperature. For a multipurpose tool that analyzes sleep rate and more, check out the Fitbit Versa 3.

What to know before you buy a sleep monitor


Sleep monitors don’t just track your sleeping patterns and quality. They can also scan various aspects of the environment to determine factors that may have an impact on your sleep. Many of these devices run the entirety of the night and track things like when you wake up or are in a lighter phase of sleep.

Some monitors include an alarm that wakes you around when your alarm would go off but when you’re in a lighter sleep phase. This allows you to wake up feeling more fulfilled and rested. The alarm is especially important if you want to optimize your sleeping efficiency and wake up at a more ideal time to get started on the day.

Certain sleep monitors also scan for blood oxygen levels and movement during sleep. Multifunctional devices can track your breathing rate, room or body temperature and certain factors like the amount of caffeine you’ve had. The data can help inform you of potentially necessary lifestyle changes to help improve your sleep quality.

Sleep phases

There are four phases of sleep, which combined, make up the entire time you’re asleep. These phases are:

  • Non-REM Stage 1: This is the transition from being fully awake to asleep. Your heart rate, breathing and the movement of your eyes slow down as your body reaches a relaxed state. This phase lasts 5-10 minutes.
  • Non-REM Stage 2: During this stage, your body temperature drops, all eye movement stops and you become less aware of the environment. This stage lasts around 20 minutes.
  • Non-REM Stage 3: Sometimes called delta sleep, this phase is when environmental factors like sound or light have very little impact on your sleep and are unlikely to wake you up. Your body becomes completely relaxed as you make your way into the deepest sleep.
  • REM: Occurring around 90 minutes after you fall asleep, REM sleep is the stage in which people are more likely to dream. This is also the stage in which the body can build or repair things like muscles, bones and tissues.

On average, a sleep cycle is 90-110 minutes. As the night wears on, the REM sleep stage becomes longer and the non-REM stages become shorter.

If you wake up during a non-REM stage, you may feel unrested or tired. That’s why a sleep monitor with an alarm is useful. It can detect when you’re exiting the REM stage and wake you up at the optimal time to improve productivity and prevent grogginess.

Types of sleep monitors

Wearable: Wearable trackers consist of rings and watches. The watch design is a great option for those who move around often, are athletic or want a larger screen display. These devices may also track your breathing or function as a GPS or traditional watch.

Ring: The ring design is more compact, though some of the larger models have a small screen. These trackers have a long battery life and an app associated with the model that stores data. Most ring trackers don’t have a smart alarm.

Bed sensor: Bed sensors go directly under the mattress or sheets and can track your movement, heart rate and environmental factors while you sleep. Some bed sensors can pair with other smart home devices or home automation systems.

Although not sleep monitors, there is some smart bedding that can also analyze your sleeping habits.

What to look for in a quality sleep monitor


Wearable sleep monitors like rings and watches are usually made from titanium or silicone. These materials are comfortable and sturdy enough to withstand the elements when worn outside. Other sleep monitors, such as Fitbits, are made from rubber or lightweight polyester. Most non-wearable sleep monitors are fabric or rubber. These materials prevent the device from moving around in between the sheets or mattress.

Battery life and portability

A sleep monitor’s battery life varies immensely. Some devices offer up to 48 hours at full charge, while others only last for around 16 hours or less.

Some non-wearable devices plug into the wall, which eliminates the need for a long battery life. However, these devices may have lower accuracy when it comes to scanning sleep quality and patterns. Devices that aren’t portable are also ineffective when it comes to monitoring your health during the day.


Many sleep monitors are compatible with certain apps. These apps have their own user interface to collect and summarize sleep- and health-related data. The best sleep apps are ones that can consolidate information, such as heart rate, sleep quality and temperature and relay it in a clear, informative way.

Not all sleep monitors are compatible with apps, so keep this in mind when picking one out. Also, some sleep apps require a monthly or yearly subscription.

How much you can expect to spend on a sleep monitor

On average, wearable sleep trackers cost $150-$250. Non-wearable trackers, such as those that slip under the mattress, usually cost around $100 since they have more limited functionality.

Sleep monitor FAQ

Are sleep monitors accurate?

A. Sleep monitors are accurate around 78% of the time. The accuracy level varies based on monitor type. Wearable trackers are usually more accurate than non-wearable options.

What’s the point of tracking my sleep?

A. Sleep monitors identify a person’s sleeping habits and patterns to help ensure the best quality of sleep. This could result in higher energy levels, less grogginess, more alertness and better overall health.

What’s the best sleep monitor to buy?

Top sleep monitor

Fitbit Versa 3

Fitbit Versa 3

What you need to know: This wearable device not only tracks sleep, but also monitors heart rate and blood oxygen levels.

What you’ll love: This Fitbit is sturdy enough for all-day use in nearly any environment. It comes with a built-in GPS and is compatible with Alexa so it can check the weather or set on-the-go reminders. When worn, it provides sleep and basic health-related data continuously, which it then breaks down to help you improve your sleep habits.

What you should consider: It comes with a music service that requires a paid subscription to use.

Where to buy: Sold by Amazon and Kohl’s

Top sleep monitor for the money

Fitbit Charge 4

Fitbit Charge 4

What you need to know: This budget-friendly touchscreen device not only monitors your sleep stages, it also tracks your heart rate during exercise.

What you’ll love: The Active Zone Minutes is a useful feature while working out because it vibrates when you reach a target heart rate. Additionally, this device can easily connect to any smartphone for a visual chart of your sleep quality throughout the night.

What you should consider: The battery life is fairly short. The sleep monitoring may be less accurate than other devices.

Where to buy: Sold by Amazon and Kohl’s

Worth checking out

Wellue Sleep O2 Monitor

Wellue Sleep O2 Monitor

What you need to know: This smart device can monitor sleep, but it also tracks your O2 levels, heart rate and body motion while you sleep.

What you’ll love: This monitor is a great way to perform your own overnight sleep test. It records information that you can then bring to a physician for additional analysis. Additionally, it vibrates when your oxygen levels reach a certain threshold, making this device useful for those who need to keep an eye on their breathing.

What you should consider: This is not a typical sleep monitor and doesn’t identify when you’re in deep versus light sleep.

Where to buy: Sold by Amazon


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Angela Watson writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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