Good quality sleep is linked to general health, mental wellbeing and even the avoidance of serious illnesses, so using a bedtime tracker to check you're getting enough rest can be a genuine help.
Wellness isn't just about doing cat yoga and drinking alt-milks, after all. Sometimes you just need a refreshing sleep to help you feel better.
Luckily, there are now plenty of different ways to track sleep, too, whether that's through a bedside monitor, a wrist-worn wearable like a smartwatch, a device that fits under your mattress or even a smart ring.
All will give slightly different insights and personalized tips on how to improve your rest time, but the options we've picked out below are worth exploring if you want to know exactly how you're sleeping – and make positive steps to improve the quality of it.
We'll be breaking down what to look for in a sleep tracker, how it manages to track your sleep accurately and the best sleep gadgets to buy. We've tested the accuracy and design of them all so you don't have to.
Update: This article was updated in October 2022 to reflect the addition of the Fitbit Sense 2, Google Nest Hub (2nd Gen), Apple Watch Series 8 and Polar Pacer Pro.
Summary: The best sleep trackers
- Best overall sleep tracker - Fitbit Sense 2
- Best mattress sleep tracker - Withings Sleep
- Best bedside sleep tracker - Google Nest Hub (2nd Gen)
- Best smart ring for sleep tracking - Oura Ring 3
- Best fitness tracker for sleep tracking - Fitbit Charge 5
- Best sleep tracker for recovery insights - Whoop Strap 4.0
- Best Apple Watch for sleep tracking - Apple Watch Series 8
- Best hybrid smartwatch for sleep tracking - Withings ScanWatch
- Best sports watch for sleep tracking - Polar Pacer Pro
Sleep tracking: Terminology explained
Before you can pick the right sleep monitor to watch over your night, you need to know exactly what you want from one. The tech involved here is much more advanced than the smartphone apps that use the accelerometer to track movement under your pillow – and, as a result, things are much more accurate.
HR versus movement sensors
Older fitness trackers used wrist movement to track sleep, but now this is all combined with heart rate monitoring – and companies like Fitbit and Withings are looking at your beats per minute (bpm) during sleep to make assumptions about duration and sleep stages.
Sleep stages are tracked by most top sleep monitors, and this means logging the amounts of light, deep and REM sleep plus any awake time – including tossing and turning.
You should cycle through these sleep stages a few times per night to feel rested – and the trackers in this guide will show this in their analysis. If you're not cycling between them – or you're missing out on some of these stages altogether – it's a smoking gun for bad sleep, and a great place to start improving.
Looking at all this data can feel overwhelming – and, when you've looked at the data for a few weeks, you'd be forgiven for wondering what it all means.
Many brands now distill your data down into a meaningful number, so you can see how your slumber stacks up. Several of the devices we've listed (Fitbit, Withings and Xiaomi) offer a single sleep score from their data.
Blood oxygen and sleep apnea
The latest data in town is blood oxygen – which is tracked using a SpO2 sensor. You'll find them on some Fitbit, Garmin and Withings models, as well as devices like Whoop and Oura.
That might sound nuts, but the amount of oxygen in your blood – or at least a dip in levels while asleep – is linked to a condition called sleep apnea. It's estimated that 22 million Americans suffer from it, and the majority don't actually realize it.
Choosing a sleep tracking wearable with an SpO2 sensor will offer up this data, so you can ensure you're not an unwitting statistic.
Fitbit Sense 2
The best sleep tracker overall
$299.95 / £269.99 | Amazon
When it comes to tech, the Fitbit Sense 2 is the best wearable sleep tracker on the market right now, and we've tested it extensively.
It uses the same tracking technology as the rest of the Fitbit line, but it also gives you the most complete experience when you're out of bed, which is why we have it as our top recommendation.
Fitbit Sleep Stages ensure that you can get a daily look at your light, deep, REM and awake times, and you can still check in on how your night compares to the last month and other people your age.
(The Fitbit app shows sleep history, stage breakdowns and detailed graphs)
The Sense is built with a tri-wavelength HR sensor on board, and uses a relative SpO2 sensor to unlock Estimated Oxygen Variation while you sleep. This is a measure of the oxygen in your blood, and large swings can be a sign of disorders like sleep apnea.
It tracks sleep stages and the time spent in each stage, as well as your heart rate throughout the night and how much you tossed and turned and turn that into a Sleep Score. Fitbit Premium users can see a breakdown of how that score was calculated in more granular detail (see above).
Generally, we've found the Fitbit Sense to produce the most reliable and actionable data of any wrist-based sleep tracker. The data can seem a little harsh, often chopping eight hours in bed down to just six hours of sleep. But you can easily see lifestyle variables in the data better than other sleep trackers.
On the Sense 2 (and the original Sense), features like the breakdown of duration, sleep stages, heart rate via sleep (plus percentage under resting heart rate) and Estimated Oxygen Variation require signing up to Fitbit Premium.
If you care about your sleep and the other health metrics Fitbit's health watch is capable of delivering, then you'll want in on this subscription package. In return, you'll get something that you can take to bed and get reliable, insightful sleep data.
The best mattress sleep tracker
$99.95 / £99.95 | Amazon
The Withings Sleep slips under your mattress and collects your sleep data, and was released back under the company's name after the buy-back from Nokia.
It's not the latest version, though. The Withings Sleep Analyzer is available in Europe and ROW, but it hasn't received FCC approval for its main sleep apnea feature. So, if you're in the US, the Withings Sleep is the only option for now.
Thankfully, it still offers the core experience, and is able to collect data like sleep duration, interruptions, light, deep and REM sleep - plus snoring, thanks to a built-in microphone.
It can tap into the Withings app, giving you a coaching program to help reduce fatigue and improve your health.
There's not a lot to pick between the Sleep mat and Fitbit's wrist-based options in our testing, but we did experience some accuracy issues with the Withings Analyzer when waking up but staying in bed.
Sleep score is a major focus, as it is on most tracking apps now. It's the most obvious way to find out whether you had a good night's sleep, and will be in red if you had a bad night. The higher the score, the better night of sleep you had.
Even better, the app helps you understand what makes a good night of sleep by telling you how to raise your Sleep Score.
The Withings Sleep is the same device as the Nokia Sleep, which we've tested and is the same device with the Nokia name on the front of it.
If you want an idea of what the Withings Sleep is going to be like to use, definitely go have a read of our Withings Sleep Analyzer review.
Google Nest Hub (2nd Gen)
The best bedside sleep tracker
$54.99 / £44.99 | Google
If you're not a fan of wearing a tracker or having something live under your mattress, the Google Nest Hub (2nd Gen) is a superb pick - and one of the most accurate we've ever tested.
Primarily, the smart display's Motion Sense is doing the tracking, using a low-energy radar to detect movement and breathing rate. Then, this radar data combines with Google's Sleep Sensing, which takes into account light, sound and room temperature to deliver a comprehensive verdict on your slleep.
The end result is a detailed on-device summary of your night's sleep - including sleep stages and suggestions on how to improve your rest - with this raw data also feeding into the Google Fit app to give you a historical view of your trends over time.
There's no kind of sleep score here, with Google instead opting to summarise your sleep with one of either 'Restful', 'Fairly Restful' or 'Restless'. And, in some senses, we prefer it to a score - it feels a bit more of an intuitive reflection.
We also find, on the whole, the sleep stage data to be much more consistent than many wearables. There's very few - if any - eyebrow-raising sleep stage estimates, and this makes it a much more useful tool when trying to match up with your own intuition on your readiness to take on exercise strain or a big day of work.
There's now also deeper integrations with the Google Pixel Watch and Fitbit devices available on the Nest Hub, linking information regarding exercises and calorie burn. Considering this one also acts as a smart speaker, YouTube player and also supports apps like Headspace, it's actually a really rounded device.
The only real downside is that you'll need to place this much more carefully than other devices on this list. You essentially have to have a bedside table at roughly the same height as your mattress, and, rather than being up against the wall, it'll need to be in line with your pillow in order to deliver the most accurate results. Like with mattress trackers, it does also sometimes struggle to register when you've woken up but are still in bed.
Oura Ring 3
The best smart ring for sleep tracking
$299.99 (plus monthly subscription service) | Oura
While a smart ring maybe isn't the first device you'd think of, the Oura Ring is a powerful and discreet sleep tracker that's well worth serious consideration. It's one of the sleekest ways to track your bedtime.
It's packed with sensors, too, enabling the ring to keep tabs on heart rate, movement and body temperature.
It's capable of capturing data like sleep duration, recognizing time spent in bed, sleep efficiency, resting heart rate and sleep stages. It will track naps and will have the ability to track blood oxygen when a future software update rolls out.
Based on your sleep score, Oura provides you with a simple, intuitive readiness score for the day.
That's based on more than just sleep, including heart rate variability and activity data, as well. It'll make sleep time suggestions that feel realistic, and data held up very well against the likes of Fitbit and Whoop in our testing.
Fitbit Charge 5
The best fitness band for sleep tracking
$179.99 / £169.99 | Amazon
The Charge 5 also offers Fitbit's best-in-class sleep tracking experience that we've detailed above in the Sense 2 entry. The only real difference here is the form factor.
You get Fitbit Sleep Stages, giving you a more in-depth look at your sleep. It'll track whether you're in light, deep or REM sleep, giving you actionable insights the next morning.
Plus, you can compare your results against people of a similar demographic, as well as your average night's sleep over the past 30 days.
If you're signed up for Fitbit Premium, that will get you those extra blood oxygen variation insights here, too.
What we like about Fitbit's sleep tracking is that it learns your behavior over time, and will start giving you more and more personalized feedback for getting better rest.
Tracking accuracy is as good as it gets from the wrist, and the intuitive companion app, where the sleep graphs are held, completes a package that makes this one of the best fitness trackers for sleep.
Whoop Strap 4.0
The best sleep tracker for recovery insights
$18 / £18 per month | Whoop
The Whoop Strap 4.0 is a completely different proposition to most on this list. First and foremost it's a workout tracker, which can be worn in multiple locations on the body and is the choice of CrossFit enthusiasts and functional fitness types for tracking hardcore sessions.
But, while you can read about those aspects in our best gym trackers guide, sleep tracking is also a huge part of the Whoop Strap 4.0's makeup.
A bit like the Oura Ring, the Whoop Strap 4.0 will assign a sleep quality score based on time in bed, hours asleep, sleep needed, disturbances, sleep efficiency and how much time you spent in individual sleep stages.
You'll then get recommendations on how to gain optimal sleep to aid your recovery from a tough day of training.
There's also a sleep coach to help make sure you get the right amount of sleep, though they can be demanding at times when you're not hitting an optimal sleep goal.
This is all used to advise you when to train, and when to take a day off. This is presented with a single number – your Strain Score.
Of course, this isn't a band for those looking to take a few more daily steps (it doesn't actually track steps at all) – but, for seasoned gym-goers, it's the best option on offer.
It costs more than your average Fitbit, however. There's a hefty monthly subscription fee, despite the device itself being free of charge, and we're not totally convinced about the total value.
Accuracy is good, though, and if you're seeking out a less intrusive sleep tracker that's comfortable to take to bed, there are lots of things to like about the Whoop 4.0.
Apple Watch Series 8
Best Apple Watch for sleep tracking
Technically, you're able to track your sleep using any Apple smartwatch running watchOS 7 and above. However, the Series 8 is by far the most complete Apple Watch outside of sleep tracking, which is why it's our top recommendation.
Since being introduced a couple of years ago, Apple has gone on to massively improve its sleep tracking. Gone are the days when you really needed an Apple Watch sleep tracking app, with stages being added in watchOS 9, adding to light information and respiration rates.
It's also very accurate, closely rivaling Fitbit in our tests. In fact, it often matched Fitbit minute for minute with unwavering reliability - it's just the detail that doesn't quite match up.
It's a little more basic than what you'll find on Fitbit's watches - or other sleep monitoring watches, for that matter.
That being said, the Apple Watch is a comfortable device to wear to bed. Again, it's not quite as light or small as some options, but it's not a watch that feels alien to keep on.
And that's especially true if you're wearing a light band, such as the sporty silicon or knitted loops - unless you're an Apple Watch Ultra owner, anyway.
The best hybrid smartwatch for sleep tracking
$329.99 / £279.99 | Amazon
The Withings ScanWatch took a long time to receive approval for its ECG-based heart rate monitoring, but, now it has it, this has become a top option for those seeking a hybrid smartwatch that can double up as a solid sleep tracker.
It's capable of tracking sleep duration and the time spent in the key deep, light and awake stages. It will also score duration, depth, regularity of bedtimes and interruptions. You don't get the ability to view REM sleep stage data, however, which is an odd omission.
With a heart rate on board, the ScanWatch will also monitor average sleep hearing rate, while there's a SpO2 sensor to help monitor breathing disturbances and potentially detect signs of sleep apnea. Those sleep disturbances are scored on a color-coded scale.
Unless you’re someone who really detests having anything on their wrist in bed, the ScanWatch's slim physique makes it very comfortable to wear to sleep. There’s an alarm, as well, so you can be woken by a gentle vibration on your wrist, instead of blaring noise.
In our testing, accuracy wasn't perfect, but it's not terribly far from Fitbit's standard.
The data is easy to digest, as shown above, but sadly the insights aren't quite as meaty as we'd like. However, if you're looking for something that's good at the basics when it comes to sleep, the ScanWatch is by no means a bad call.
What you'll get with the ScanWatch over other Withings hybrids is that SpO2 sensor, which, in truth, might not be a dealbreaker for everyone. If you do want the best insights, though, that's what you'll get here.
Polar Pacer Pro
The best sports watch for sleep tracking
$299 / £249 | Amazon
The Polar Pacer Pro is a sports watch first and foremost, obviously, but it's also a watch that pays close attention to the importance of sleep in relation to recovery, helping you get the most out of your training.
And while Garmin is making good strides in this area - feeding into great recovery metrics like Body Battery, Training Readiness - there are still a few many inconsistencies with aspects like sleep stages for us to really recommend it. Polar, on the other hand, is a bit more reliable.
The Pacer Pro, like the rest of the Polar lineup, uses the onboard accelerometer to determine when you're asleep, then generating a raft of data and insights.
It will give you a breakdown to show your duration, sleep and awake times plus an overall score for your sleep. It also includes a Nightly Recharge feature (below) that delves deeper into the recovery of your automatic nervous system.
It was pretty reliable in detecting sleep and wake times in our testing and clocked interruptions as well, while the overall sleep score tended to match how we felt.
Unfortunately, these rich sleep tracking features do seem to come at the expense of battery life, though. It's quite a far way behind Garmin and Coros sports watches in this department and is definitely something to keep in mind when comparing the top options.
Still, if you can live with charging after around five days, you'll get more detailed, reliable sleep tracking than these rivals in return.