Exactly What Does A Sleep Tracker Monitor?

A good night’s sleep is essential for overall health and well-being, but getting the rest you need can be tricky. Over 40% of adults fall asleep unintentionally during day hours at least once a month, says a report [source]. Despite feeling exhausted, many people underestimate the amount of sleep they need.

An excellent way to find out how much restorative sleep you need is by tracking your sleep with a wearable device or app. There are a lot of talks these days about sleep trackers and their ability to track your sleep and help to improve your quality of sleep. 

Surprisingly, 30%-50% of people say that they believe in sleep tracking apps to improve their sleep patterns and seek help for better rest when needed [source]. But do these devices really work, and what do they monitor?  

In this post, let’s take a look at what sleep trackers are capable of tracking and how they can help you get the restful night’s sleep you deserve.

Related: Dos And Don’ts Of Sleep-Tracking Devices

How Does A Sleep Tracker Work?

Using accelerometers, sleep trackers will estimate the quantity and quality of your sleep. The data collected by the accelerometers is analysed using an algorithm with the help of factors such as the amount of time you spend awake during the night and how often you move around. 

This information is then used to estimate your total sleep time and sleep quality. As a result, a sleep tracker helps you understand your sleep needs and ensures you get a good night’s rest.

Different types of sleep trackers on the market will help you get better sleep habits. Depending on what kind of sleep tracker you use, there are several ways to track your sleep. 

The most basic sleep trackers measure the time we are asleep vs. when we are awake. However, more sophisticated devices also track our heart rate and other biometrics in an attempt to improve accuracy.

Whether you use a simple wrist tracker or a sophisticated monitor, most devices use three key areas: sleep cycles, heart rate, and breathing, and they provide a wealth of information about your sleep habits.

So, What Does A Sleep Tracker Monitor Exactly?

One can have a better understanding of what they monitor only after gaining explicit knowledge of the sleep phases.

Phases of Sleep are typically divided into four stages: 


  1. Stage 1: This stage is the lightest stage of sleep and usually only lasts for a few minutes. People in this stage can still be easily awakened.
  2. Stage 2: This stage is a bit deeper than Stage 1. During this stage, eye movement stops, and brain waves start to slow down.
  3. Stage 3: It is the deepest and most restorative stage of sleep. Delta waves start to appear.
  4. Stage 4: REM sleep is when people dream. During this phase, brain activity increases, and breathing becomes faster and irregular. Eye movements also become more rapid.

Now, let’s look at what sleep trackers monitor.

Though many sleep trackers on the market today have different features, most of them share some key features; these include:


  • Tracking sleep phases:

Have you imagined waking up feeling refreshed and well-rested every morning without hitting the snooze button a dozen times? That’s the promise of the REM sleep tracker. 

The REM sleep tracker uses sensors to track your brain waves as you sleep and will wake you up more easily without breaking your crucial REM sleep cycles.

  • Quality of sleep:

If you’re worried about your sleep quality, a sleep tracker could be a helpful addition to your nightly routine. They monitor your sleep and provide feedback on how well you’re sleeping. 

They can also detect when you’re tossing and turning and when you’re waking up during the night. This information will help identify patterns that may be interfering with your sleep quality. 

For example, if you find that you’re consistently waking up at the same time each night, a sleep tracker can help you to identify this pattern and take steps to address it. 

  • Duration of sleep:

Most people are familiar with the standard morning alarm clock. But for some, this simple device is insufficient to ensure a restful night’s sleep. For them, there is a new breed of activity tracker, which not only monitors the time you are inactive but also provides valuable data about your sleep patterns. 

These trackers use sensors to detect when you are asleep, how many times you wake up during the night, and even provide information about how long it took to fall asleep. This data will be invaluable for those who want to optimise their sleep routine.

  • Environmental factors:

One often-overlooked culprit of poor sleep quality is the environment in which we slumber. Fortunately, sleep trackers can now record factors such as temperature and ambient light. By tracking things like temperature and light levels, these devices can help you optimise your sleeping environment for better rest.

Yes, a sleep tracker is a valuable tool that will make it easier to effectively track and optimise your sleep patterns and help you identify sleep issues and disorders. By using a sleep tracker, you can better understand your sleep habits and make the necessary changes to improve your overall quality of sleep.