The Best Sleep Trackers 2021

Updated on March 3, 2021 While all product recommendations are chosen independently, we may receive compensation for purchases made through our site. Learn more about our affiliate program here.

We live in an era of data. Our ability to track, count, and analyze all types of activities has exploded, providing us with more information to optimize how we work and live. Though trackers have gained more popularity for how they can monitor athletic performance, tracking and data is being recognized more and more for their potential to improve sleep.

If you’re thinking about starting to keep track of your sleep and look for ways to improve it, you’ll find no shortage of options for devices that can help. Unfortunately, the number of these devices can be overwhelming.

For that reason, in this guide we’ll present our picks for the best sleep monitors including both wearable and non-wearable options. We’ll also describe how sleep trackers work, the types that are available, and the features that you can look for.

Our Top Picks

ManufacturerModelTypeKey FeaturesPrice
ResMed S+Non-wearableNon-contact device, environment monitoring, sleep coaching$94.99
Nokia SleepNon-wearableIntegrates with WiFi devices, advanced data collection$99.95
SleepScore MaxNon-wearableNon-contact system, significant sleep tracking and coaching$149.99
VersaWearable24/7 tracking, heart rate and movement monitoring$199.95
Alta HRWearableSleek design, movement and heart rate tracking for sleep and fitness$149.95
A370WearableAdvanced activity data, tracks sleep stages$149.95
Steel HRWearableStylish design, activity and sleep tracking and alarms$179.95

How Do Sleep Trackers Work?

All sleep trackers gather data while you are sleeping, but the exact way they gather information and the type of data they collect can be different depending on the type of sleep tracker.

Detecting movement is one of the main ways that sleep trackers work. For devices that you wear (such as fitness trackers that are a wristband), your movement is tracked using the accelerometer in the device. This is the same technological component that allows the device to provide you with statistics about a run or hike or bike ride. If you are in bed and the device detects no movement for an extended period, it can indicate that you are asleep during that time. Non-wearable sleep trackers also generally use movement sensors to achieve the same goal.

In addition to larger movements of the body, some trackers may try to monitor smaller movements in the chest area in order to try to keep track of your breathing.

Many sleep trackers also gather data about your heart rate. Wearable devices may have a heart rate monitor for this information, and non-wearable trackers often use ballistocardiography (BCG) to help keep track of heart rate. BCG counts very slight movements of the body that occur when the heart beats.

These are the primary data sources that sleep trackers monitor. This data is then analyzed using algorithms that attempt to determine whether or not you are asleep based on the data. They then can generate reports, usually in a smartphone application with an easy-to-read interface, about your total amount of sleep and sleep interruptions. This data is tracked nightly so that you can see patterns and trends in your overall sleep.

Algorithms using this data may also try to determine the quality of your sleep by analyzing your sleep stages. When we sleep, we progress through different stages of sleep within one sleep cycle (usually around 90 minutes in total). By using data about breathing and heart rate, some trackers hope to identify how long you spend in each sleep cycle.

While sleep trackers collect a lot of data, there is still some disagreement about how accurate that data really is. For example, with movement, it is possible to be in bed and not moving but not actually be asleep. Similarly, some people move even while sleeping. Though the algorithms attempt to account for these things, there can be margin for error in the final analysis. And while tracking movement is relatively easy, tracking heart rate and breathing can be more complex, making it unclear how well sleep trackers can monitor your sleep cycle.

Types of Sleep Trackers

Though there are dozens of specific sleep tracking products on the market, these can generally be broken down into three basic types.

  • Sleep tracking apps: you can download certain apps to your smartphone that attempt to monitor your sleep without needing to buy any additional equipment. These may use the accelerometer in your phone and/or the microphone to detect sound. Though the cheapest option, these apps usually are the least accurate.
  • Wearable sleep trackers: wearable sleep trackers are usually the same as wearable fitness trackers and can serve both purposes. These devices are designed to monitor movement and in many cases heart rate as well. These are often worn as a wristband or a smaller device that can fit in your pocket. A watch with these functions may be referred to as a sleep tracker watch. An app or website that shows you the data is typically part of the package that comes with these wearable devices.
  • Non-wearable sleep trackers: by non-wearable, we mean that these sleep trackers do not directly attach to your body. Instead, they may be attached to your bed, specifically above your mattress but underneath your sheets. Or they may sit on a nightstand or table near your bed. They use different types of sensors to keep track of your movement, heart rate, and breath. Some may have additional features relating to tracking temperature, sound, or lighting in your bedroom to provide more data to try to enhance your overall sleep environment.

Because these products are still relatively new and because there is still much to be learned about sleep science, there is no consensus about which offers the “best” information. However, in general, both wearable and non-wearable devices have a greater capacity to collect meaningful information than standalone smartphone apps.

What Are the Features of Sleep Trackers?

It’s tempting to think that all sleep trackers are the same and have the same features, but there can actually be significant diversity in these products. While there’s a lot of overlap in the design and function of these devices, the way that they work and the features that they offer are important to take note of when shopping for a tracker.

Some of the features to keep in mind and to look for include:

  • Enhanced sleep tracking: at a minimum, a sleep tracker should be monitoring your movement. If it can also keep track of other details like your breathing or heart rate, these can be useful for more detailed data analysis. If you want a more complete picture of your sleeping environment, look for a tracker that also is able to monitor sound levels, lighting levels, room temperature, and/or air quality.
  • Advanced analytics: a good sleep tracker doesn’t just gather data, it helps you understand what that data means. The best sleep monitors provide you with clear analysis of how long you sleep, how much your sleep was disrupted, and in many cases information about your sleep stages. Some trackers will combine this type of information into an overall sleep grade or score to help with day-to-day comparisons. Wearable devices may also be able to integrate data about your fitness activities to look for relationships with your sleep quality.
  • A quality smartphone app: most sleep trackers come with access to an app and/or website that lets you view your sleep data. Look for an app that is easy to use and that is visually appealing. Ideally, the app should allow you to configure the dashboard to easily view the data that is most relevant for you.
  • Useful alarms: sometimes called smart alarms, many sleep trackers use data in real time in order to wake you up at a time that fits better with your sleep cycle. So rather than selecting a hard and fast time for the alarm to go off, it may wake you up when it detects that you’ve finished a particular sleep stage. Other alarm features may include more gradual wake-ups or vibrating alarms that are less disruptive.
  • Design and comfort: if you have a wearable device, you want its look and feel to be something that encourages you to wear it all the time. And with a non-wearable, it’s important that the tracker doesn’t disturb your feeling of comfort on the mattress.
  • Battery life: your device can only collect data if it has battery, so look for models that charge quickly and hold their charge for an extended period.
  • Water resistance: if you live in a rainy climate or otherwise are worried about exposing your wearable device to water, look for one with water resistance or an easy-to-use waterproof case.

Top 4 Wearable Sleep Tracker Reviews

Fitbit Versa

Why We Picked It

Fitbit is one of the best known names in wearable tracking devices, and the Fitbit Versa is their smart watch. Its ability to track motion and heart rate allows it to provide monitoring of sleep stages while also providing a smart alarm and tips to improve sleep. It also offers a huge array of features for improving fitness and wellness while tracking those activities.

Who It’s For

The Fitbit Versa is best for people who want a 24/7 device that provides data about all different aspects of life and wellness.

Who It’s Not For

This device is not for people who only want to focus on sleep or who do not like wearing a watch. It also does not monitor your sleep environment, so it is not a good fit for people who want to monitor that along with their movement and heart rate.


Fitbit Alta HR

Why We Picked It

The Fitbit Alta HR is a sleek tracking wristband that monitors fitness and sleep data. It has the ability to track your movement as well as your heart rate, and the company’s algorithms can use this data to track your sleep stages and quality. It offers silent alarms to wake you up gently and has a longer battery life than many other wearable devices.

Who It’s For

This device is best for people who want a lower-profile wearable tracker that can monitor data throughout the day and integrate this into a bigger picture about overall wellness, including sleep.

Who It’s Not For

The Fitbit Alta HR is not for people who dislike having to wear a device on their wrist when sleeping. It also does not track information about your sleep environment (such as temperature, snoring, lighting, etc.).


Polar A370

Why We Picked It

The Polar A370 wearable tracker is a compact wristband that keeps detailed data about your activity during the day as well as your sleep. It monitors sleep through its use of 24/7 heart rate monitoring and through its accelerometer. It helps you keep track of the length and quality of your sleep.

Who It’s For

This tracker is best for people who want a full picture of their overall daily activity and the ability to coordinate all of that data to improve their health through better fitness and sleep. Like all wearable devices, it provides more useful information for people who share a bed with someone else.

Who it’s Not For

This tracker is not for people who want to monitor their breathing, snoring, light, temperature, or other aspects of their overall sleep environment.


Nokia Steel HR

Why We Picked It

Although the Nokia Steel HR does not offer the same detailed sleep information that comes from other trackers, it is a far more stylish option that is also water-resistant, making it more appealing for people who want to wear the tracker 24/7. It uses both HR and movement monitoring to collect data about your sleep patterns.

Who it’s For

This tracker is best for people who want a wearable tracker for their activity and sleep but who find many of the other models to be unsightly or informal.

Who It’s Not For

This tracker is not a good choice for people who want a smaller, lower-profile wristband or who want detailed data about their sleep environment in conjunction with their sleep patterns.


Top 4 Non-Wearable Sleep Tracker Reviews

Non-wearable sleep monitors don’t keep data about other daily activities, but they can provide a wealth of information about your sleep environment. Our top 4 non-wearable sleep monitors are described below (in no specific order):

ResMed S+

Why We Picked It

The ResMed S+ is a non-wearable device for sleep tracking that does not require putting any sensor on your bed. For this reason, it is called a non-contact sleep tracker. This avoids any concern with the comfort of using other types of wearable or non-wearable trackers. The S+ system integrates with an app and has many features that are designed to improve your sleep habits including a Smart Alarm, a built-in mentor to offer sleep tips, and a Relax to Sleep feature that coordinates sounds with your breathing.

Who It’s For

The S+ is ideal for people who do not want to wear a tracker or put anything under their sheets. It’s also good for people who want a lot of active feedback and tools to help them fall asleep and wake up gently.

Who It’s Not For

The S+ isn’t the best fit for people who do not have a convenient place to place the device and plug it into the wall (since it needs continuous AC power) or who do not want to have it synced to their phone all night.


Nokia Sleep

Why We Picked It

The Nokia Sleep tracker monitors a broad range of data including about your sleep environment as well as your movement, heart rate, sleep cycles, snoring, and breathing. It offers in-app sleep coaching and tips and works with other WiFi-enabled devices, including Alexa, allowing you to automate things like lights and temperature in your bedroom.

Who It’s For

This tracker is a good option for people who want a non-wearable yet non-disruptive option to put under their sheet. It is a top choice for people who want a tracker that easily integrates with other WiFi-connected processes in the home.

Who It’s Not For

This tracker won’t collect data as well for couples, and many of its features will not be as useful if you do not use many WiFi-based “smart home” technologies.


SleepScore Max

Why We Picked It

The SleepScore Max system uses sonar and radio-frequency technology to monitor your movement and breathing. It also keeps track of your sleep environment with its non-contact sensor that sits near your bed. As the company name implies, they use this data to generate Sleep Score through their app and offer tips to improve your sleep.

Who It’s For

This is best for people who sleep alone and who want a non-contact and non-wearable option for keeping track of their sleep.

Who It’s Not For

It’s not for people who do not have a convenient place to plug-in and keep the device near their bed. It also does not work for two people at the same time, and it is not possible to use two of the machines in the same room at the same time.


Top picks

1 ResMed S+ $94.99
2 Nokia Sleep $99
3 SleepScore Max $149
4 Fitbit Versa $199
5 Fitbit Alta HR $149
6 Polar A370 $149
7 Nokia Steel HR $179
*Prices without discount/promo applied.
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