How Does Fitbit Track Sleep? (Process Explained!)

Fitbit smartwatches and activity trackers have the ability to track a lot of activities, and sleep happens to be one of them. In my opinion, Fitbit has made a significant effort to enhance its sleep feature for the benefit of users. Many Fitbit users, particularly those who are new to the device, are curious about how it is able to track their sleep. So, how does Fitbit track sleep?

Fitbit tracks your sleep by using heart rate readings after detecting an hour of complete stillness in bed. By analyzing both movement and heart rate data, it can provide more accurate information about your sleep stages, including Light, REM, and Deep sleep.

The introduction of sleep tracking on Fitbit was aimed at assisting users in comprehending their sleep patterns and subsequently identifying ways to enhance their sleep quality for optimal rest.

3 Best Fitbit for Sleep Tracking

 Fitbit Charge 5Fitbit LuxeFitbit Versa 2
Display1.04-inch colored AMOLED0.76-inch colored AMOLED1.4-inch colored AMOLED
SensorsHeart rate monitor, SpO2, 3-axis accelerometer, etc.SpO2, 3-axis accelerometer, heart rate monitor, etcHeart rate monitor, SpO2, 3-axis accelerometer, etc.
TrackingSleep, blood oxygen levels, calories burned,Sleep, calories  burned,Sleep, blood oxygen saturation, calories burned,
Battery LifeUp to 4 days on smartwatch modeUp to 7 days on smartwatch modeUp to 5 days on smartwatch mode
 Check on Amazon Check on Amazon Check on Amazon

All Fitbit smartwatches and activity trackers can monitor sleep including the kid’s model (Fitbit Ace 3).

While keeping an eye on your sleep the Fitbits on the table provided above will also monitor your blood oxygen levels (with the SpO2  sensor), movements (with the 3-axis accelerometer), and calories burned while resting. All this data will be presented on the Fitbit app the next morning.

Fitbit Charge 5, Fitbit Luxe, and Fitbit Versa 2 will not only provide you with helpful sleep reports but also your sleep scores which you can use to better your sleep.

How Does Fitbit Know that Am Asleep?

Your Fitbit will begin monitoring your sleep by detecting when you have stopped moving for an hour. It will then start recording your sleep by analyzing your heart rate, muscle movements, and brain activity.

With the help of the set algorithm, Fitbit trackers can determine your heart rate variability (HRV). In addition, with the Heart Rate Variability, Fitbit will make it easy to tell whether the body made moves between sleep levels.

To be able to track sleep as accurately as possible you need to have your Fitbit on the wrist throughout the night.

It is worth noting that Fitbit calculates your total sleep time by subtracting the time you were awake or restless from your overall time spent asleep.

Fitbit devices that sleep do it in stages or cycles, let me discuss each sleep cycle for your better understanding!

Fitbit Sleep Stages Explained

Sleep stages or cycles on Fitbit are three, namely Light, Deep, and REM sleep. Let’s discuss them below!

Sleep Stage 1: Light sleep

This is the sleep level where you start to fall asleep as the body slows down. At this stage, you can be easily woken up and when you do Fitbit will record you are awake. At this stage, you are still aware of what’s going on around you. This stage is important because it is where you experience physical and mental recovery.

Sleep Stage 2: Deep Sleep

Deep sleep is the stage where your breathing slows, your body doesn’t respond, and muscles relax. In addition, it is where your heart rate becomes regular. This sleep stage is crucial because it boosts the immune system, helps with physical recovery, and improves memory.

Sleep Stage 3: REM Sleep

As the name suggests: in Rapid Eye Movement (REM), the eyes move side to side in this sleep stage. Your heartbeat increases and your brain becomes very active hence the dreams. In addition, your body muscles are so much inactive making it difficult to retrieve from dreams.

How to Check Sleep Stats on Fitbit

Accessing sleep stats or results on Fitbit each morning is very easy and can done from the app on the phone. Follow the simple steps highlighted below to check your sleep stats on Fitbit:

  1. Open the Fitbit app on your paired phone and sync Fitbit.
  2. Tap on the Today tab.
  3. Select the Sleep Entry option. This option will direct you to a page with detailed sleep data.

You can utilize the graphs to view your sleep pattern, the length of your sleep, and the different stages of sleep you experience.

Beneath the graph, there are cycles that provide a breakdown of the sleep stages you go through during the night.

Frequently Asked Questions

1. How Accurate is Fitbit Sleep

Fitbit watches are able to provide an estimate of your overall sleep quality by monitoring your movements and heartbeat. This estimation can vary depending on various physical and psychological factors. Therefore, accuracy is an important consideration when discussing how Fitbit watches track sleep. Unfortunately, research shows that Fitbit watches don’t track sleep 100% accurately. The latest Fitbit smartwatches and trackers, such as the Versa 4 and Sense 2, are found to have a sleep accuracy level of 69%. While not perfect, this level of accuracy can still provide valuable insight into your sleep patterns.

2. How Do I Improve Sleep Tracking on Fitbit?

To improve sleep tracking on Fitbit Inspire 2, Inspire 3, Charge 4, Ace 3, Sense, and Versa 2, it’s best to adjust the sensitivity setting to the maximum level using the Fitbit app. This simple step not only enhances sleep tracking accuracy but also optimizes the overall user experience.

3. Why is My Fitbit Not Tracking Sleep Consistently?

To ensure accurate sleep tracking with your Fitbit, it is important to wear it on your non-dominant wrist and make sure the bands are properly adjusted. The bands should not be too tight or too loose. By following these steps, you can consistently track your sleep patterns.

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Jashon Kanaiza

I’m Jashon Kanaiza, a lover of life, books, gadgets, and coffee. I spend hours testing, researching, reviewing, and troubleshooting wearable tech by an array of brands. My goal with JayFinity is to help you push your wearable to its limit. From tips to how-to guides to reviews, you deserve the best wearable information – without a paywall behind it.

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