Best sleep tracker 2021: top tech to monitor your sleep habits

We round up the best sleep trackers for every occasion – from subtle wearables to budget sleep trackers, to under-mattress solutions

best sleep tracker: woman checking her Fitbit in bed
(Image credit: Fitbit)

The best sleep trackers can give you an insight into what's going on while you snooze – and how it impacts you long-term. Some can even offer advice or support on how best to improve your sleep hygiene although none can (yet) force you to go to bed at the same time each night. Still, they can hold you accountable and demonstrate that a difference sleeping well can make to your energy levels the next day. While there's some overlap with today's best fitness trackers, this guide focuses on the devices that shine when it comes to monitoring your nighttime habits in particular.

Sleep is incredibly important and sometimes underrated. While most of us put the effort into eating better and exercising more, it's sleep that also helps us fend off illnesses, feel better mentally and physically, as well as simply give us the energy to go about our day. 

For most people, the Fitbit Inspire HR is the best sleep tracker. It also functions as a fitness tracker during the waking hours, and can keep an eye on how you sleep, thanks to its heart rate tracking monitoring your different sleep stages. While it's not 100% accurate, it's a solid all-rounder for the majority of users.

Alternatively, there are dedicated sleep trackers such as the Withings Sleep Analyzer, which focuses solely on monitoring your sleep. If you want more from your device, you could also consider the Kokoon Sleep Headphones – our current best sleep headphones pick, which also help monitor your sleep as well as offering some constructive assistance in helping you sleep better.

If you're here because you're struggling to sleep, you might also want to explore our ranking of the best mattresses, or perhaps pick up one of the best weighted blankets, which work wonders for some restless sleepers. If not, read on for some more buying advice, followed by our pick of the best sleep trackers 2021. 

How to choose the best sleep tracker for you

There's no shortage of different sleep trackers out there. Catering for mostly every budget as well as lifestyle, it's important to know exactly what you want it to do for you before you make a purchase. Here's a brief overview of what to consider. 

Know your budget. It's a common thing to consider with any technological purchase but it's important that you think about how much you want to spend. Sleep trackers can cost as little as £25-30 but they can also cost hundreds of pounds. Don't feel obliged to spend a lot unless you really need all the features.

Consider the features you want. Many sleep trackers do far more than just track your sleep. They also tend to track things like your steps each day, or even double up as smartwatches. It's important to know if you need these features or not as generally the more features, the more expensive the purchase. 

How comfortable the tracker is. Do you want to wear a wristband all night? How about a full-on smartwatch? Either is perfectly possible but if you're a light sleeper, you may feel uncomfortable doing so which will then affect your ability to sleep. An under the mattress solution may be a better option here. 

The best sleep tracker 2021

Black Fitbit Inspire HR fitness band and sleep tracker

(Image credit: Fitbit)

1. Fitbit Inspire HR

The best sleep tracker for most people

Specifications
Max battery life: 5 days
Heart rate monitoring: Yes
Notifications: Yes
Reasons to buy
+Comfortable fit+Great battery life
Reasons to avoid
-Not 100% accurate-Not the most stylish

The Fitbit Inspire HR is one of the best Fitbits out there right now and its sleep tracking is convenient, effective, and easy to use. Simply wear the device all day and the wearable will do all the hard work for you. It'll track your steps and calories burned, and – most importantly – it'll monitor how well you sleep through the night. Heart rate monitoring certainly helps with monitoring your sleep but it's not 100% accurate. That's because sometimes if you're simply resting and still, the Fitbit Inspire HR can mistake that for sleep. That's a common issue with any wearable device though and this is still a great purchase for anyone looking for some guidance. It's slim enough to not feel too imposing at night too. Head to our Fitbit Inspire HR review for more info.

best sleep tracker: Withings Steel HR Sport

(Image credit: Withings )

2. Withings Steel HR Sport

The best premium sleep tracker watch

Specifications
Max battery life: 25 days
Heart rate monitoring: Yes
Notifications: Yes
Reasons to buy
+Powerful fitness watch+Sleep score system
Reasons to avoid
-Uncomfortable design for sleep-Overkill for some

If you want a smartwatch that also tracks your sleep comprehensively, the Withings Steel HR Sport is a fantastic if somewhat cumbersome option. It's a full-sized watch so it won't be the comfiest of things to wear if you lean on your wrist at night, but it tracks very accurately. That's thanks to automatic sleep monitoring that looks at your light and deep sleep cycles, detects any interruptions, and how regular they become. Each morning, you can enjoy some deep insight into how you're doing each night. 

As well as that, the Withings Steel HR Sport is a powerful smartwatch for the active user. It tracks many different sports, has fantastic battery life, and estimates your ability level each step of the way. For those simply wanting to track their sleep, it's overkill, but if you want an all-in-one solution, it's great. 

Fitbit Inspire 2 band in white

(Image credit: Fitbit)

3. Fitbit Inspire 2

The best budget sleep tracker

Specifications
Max battery life: 10 days
Heart rate monitoring: Yes
Notifications: Yes
Reasons to buy
+Easy to use interface+Comprehensive sleep tracking for price+Comfortable
Reasons to avoid
-Small display-No GPS-Needs Fitbit Premium to get most from it

A little long in the tooth, the Fitbit Inspire 2 remains a reliable option if you want a budget-priced Fitbit that offers sleep and fitness tracking. It's a little basic, lacking GPS and Fitbit Pay but as we explore in our Fitbit Inspire 2 review, for sleep tracking, you can't go wrong. It's sufficiently lightweight and comfortable enough that you won't notice wearing it at night. By doing so, you receive extensive stats via the Fitbit app each morning. This includes a score out of 100 to show how well you slept, the length of time you were asleep, along with a breakdown of when you achieved REM sleep and when you were sleeping lightly. Upgrade to Fitbit Premium and you can view your sleeping heart rate too, which can be very useful. 

Withings Sleep Analyzer mat, and app shown on smartphone

(Image credit: Withings )

4. Withings Sleep Analyzer

The best non-wearable sleep tracker

Specifications
Max battery life: N/A
Heart rate monitoring: Yes
Notifications: No
Reasons to buy
+Unintrusive while sleeping+Very accurate 
Reasons to avoid
-Sleep tracker only-Requires power source

If the idea of wearing a wrist strap all night is unappealing then the Withings Sleep Analyzer is the solution for you. You slip it under your mattress, plug it in, and leave it to do all the hard work for you, allowing you to sleep encumbered. Thanks to that, it offers far more advanced sleep tracking than its competitors with an in-depth analysis of your sleep cycles, durations, and any interruptions. 

It's also able to detect any snoring episodes as well as spot any signs for sleep apnea, an underdiagnosed condition that can be a huge problem if left untreated. In terms of sheer sleep tracking power, you can't go wrong with the Withings Sleep Analyzer but it is purely a sleep tracker. That means it's a bit of an expensive purchase to track one issue through your day, but we appreciate that its app ties into others well, giving you insight into your general health and body performance all day long. 

There's also very little else out there that's quite as accurate as the Withings Sleep Analyzer and the fact it's so unobtrusive yet effective is very appealing. Head to our Withings Sleep Analyzer review to find out more.

Fitbit Charge 4T3 Awards 2021 winner badge


(Image credit: Fitbit)

5. Fitbit Charge 4

The best sleep tracker with complete fitness tracking features

Specifications
Battery life: 7 days
Heart rate monitoring: Yes
Notifications: Yes
Reasons to buy
+Extensive sleep tracking features +Excellent app+Good for lots of different sports
Reasons to avoid
-Overkill if you just want to track sleep-Slightly annoying capacitive 'button'

If you want a sleep tracker that does (a lot) more, the Fitbit Charge 4 could be the device for you. Sitting at the top of our best fitness tracker guide, the Charge 4 includes GPS for tracking runs, rides and hikes, and introduces a new system for tracking intense exercise, which sits alongside the usual step counter. 

We'll assume you're mainly here for the sleep tracker features, though. On that front, there's plenty to dig into. The Charge 4 offers an overall 'sleep score', which attempts to rate your slumber each night, and – provided you've subscribed to Fitbit Premium – you can also dig into a detailed breakdown of how long you spent in each sleep stage (light, deep, REM etc.). Finally, there's a blood oxygen tracking feature that could be helpful in alerting you to health issues such as sleep apnoea. 

Xiaomi Mi Band 4 fitness band and sleep tracker in black

(Image credit: Xiaomi )

6. Xiaomi Mi Band 4

Another reliable budget sleep tracker

Specifications
Max battery life: 20 days
Heart rate monitoring: Yes
Notifications: Yes
Reasons to buy
+Low price+Long battery life 
Reasons to avoid
-Not stylish-Uncomfortable fit

On a tight budget? The Xiaomi Mi Band 4 might not have the 'wow' factor but it does exactly what you need of it, and it costs significantly less than other sleep trackers here. That instantly makes it appealing if you're not sure if you'll commit to wearing a sleep tracker every night. Like the others, it works as a general fitness tracker too so you can easily monitor your daily steps, calories burned, as well as your heart rate. It's swim-proof too proving ideal for avid swimmers.

In terms of sleep tracking, it uses its heart rate monitor alongside detecting your restful moments, before formulating a chart that picks up on sleep time, sleep depth and how many times you wake up. Like the device itself, the app isn't as stylish as the Fitbit but it's a lot cheaper. Just bear in mind that it's a little chunky for the night time.

Kokoon Sleep Headphones over-ears in black

(Image credit: Kokoon)

7. Kokoon Sleep Headphones

Headphones that also double as a tracker

Specifications
Max battery life: 13 hours
Heart rate monitoring: No
Notifications: No
Reasons to buy
+Extensive sleep-related features+Also works as headphones throughout the day+Very comfortable
Reasons to avoid
-Doesn't track fitness-Headphones rather than exclusive sleep tracker-No good for side sleepers

If a wearable doesn't appeal and you don't want to plug something in under your mattress, there's always the Kokoon Sleep Headphones. They're an expensive but highly competent pair of headphones that offer extensive Active Noise Cancellation features as well as some very clever sleep tracking tools. Each earcup features EEG brainwave sensors built in so once they come into contact with your ears, the headphones can figure out when you've fallen asleep, how long it took, and how deeply you're sleeping.

It learns as it goes along, recommending programs and audio from the dedicated app that – in theory – will help you rest and sleep better. Basically, it's like a sleep therapist, allowing you to find the music and white noise that works best for you before tracking how you're doing so you know exactly what works for you.

It's an expensive solution though and if you want something that tracks the rest of your day, this isn't the gadget for you. These are purely at their best when you're relaxing. Head to our Kokoon Sleep Headphones review for more info.

Fitbit Ace 2 band in blue with yellow details

(Image credit: Fitbit Ace 2)

8. Fitbit Ace 2

The best sleep tracker for kids

Specifications
Max battery life: 5 days
Heart rate monitoring: No
Notifications: No
Reasons to buy
+Fun design+Motivational features
Reasons to avoid
-No heart rate monitoring-Chunky design

Have you got a child who's struggling to sleep? The Fitbit Ace 2 can work well as a fun motivational tool, showing your child what they're achieving each night by sleeping. Working much like older Fitbit models, it keeps an eye on any sleep disturbances and provides insight into where problems may lie. It also works well as an exercise tracker throughout the day too.

There's no heart rate monitoring which means sleep tracking may be slightly less accurate than with other models, but that's not a huge issue here as it's generally a guidance tool for parents and kids alike. It's basic but a good starting point if you simply want to rule out some issues or help your child feel more knowledgeable about sleep. Watch out for the chunky design if your child is sensitive about what they wear at night. 

Jennifer Allen

Jennifer Allen has been writing about tech for nearly a decade. Her specialisms include fitness wearables, Bluetooth speakers, and all things Apple.