Fitbit’s New Sleep Tracking: Testing The Alta HR

screenshot of the sleep stage graph on the fitbit smartphone App

2019 update

I originally wrote this article back in 2017. Rather than changing it all, I wanted to keep the original content for those interested in my earlier impressions, and to be able to see how Fitbit has changed if you’re interested.

However, there are some important points worth noting as you read the article:

  • I refer to the Sense and Jawbone trackers, but they were both discontinued. However, Jawbone Health is being worked on and will hopefully mark a return to wearable trackers.
  • I no longer use the Alta HR myself, preferring the Versa. You can also see how that performs in my multiple sleep tracker test.
  • I now prefer devices with a color screen rather than the thinner bands I used to.
  • In 2019, Fitbit introduced a paywall for some sleep tracking data, which has not gone down well with some users (see the Fitbit community forums for some heated debates!). I don’t know if it will last, but at the time of writing you need to pay a monthly subscription for Fitbit premium to get personalised sleep insights and some more complex data. However, the sleep data I wrote about in the original article is still available for free.

The original article

my fitbit alta

In 2017, Fitbit made some major changes to its sleep tracking. The Charge 2 HR, Blaze, Alta HR and Ionic now provide sleep stage tracking, better sleep insights and other helpful extras like sleep schedule reminders.

Like all home sleep trackers, however, Fitbit devices have historically struggled with accuracy problems, both with activity and sleep tracking.

But while some, like the Jawbone and Sense for example, appear to have fallen by the wayside under the strain of constant criticism, Fitbit appear keener than ever to improve both the accuracy and helpfulness of their devices and App.

So to find out more about the new sleep tracking, I decided to wear an Alta HR for a month to see just how accurate and useful the sleep data on the App, reminders and insights proved to be.

What I was looking for

I regularly test new activity and sleep trackers, but I also like to have one for real personal use, rather than just being a part of my ongoing tests.

And for me personally, there are a few things that make it more likely I’ll stick with one, rather than leave it in a drawer after I’ve finished reviewing it:

  • It looks good – this matters if you wear it constantly and have to take it to bed with you!
  • It feels comfortable to wear during the day and in bed.
  • It appears accurate on measurements I can test myself, such as heart rate and steps. And to a certain extent, the time I probably fell asleep, times I woke up during the night and in the morning.
  • The App is easy to use, understand and interpret.
  • The App provides useful, actionable tips to help me sleep better.
  • If there are useful reminders to take action, such as do some exercise or get ready for bed.

Some of these points apply to the specific device, of course. And others apply to all of the new Fitbit devices, such as the sleep data on the App.

Since this is intended to be a look at the new sleep tracking, rather than a detailed review of the Alta HR itself, I’ll cover it only briefly before looking at the Fitbit sleep tracking that’s the same for other devices.

Why I chose the Alta HR for the month

Having worn many different trackers on my wrist at night, I know that I prefer them to be as comfortable and unobtrusive as possible.

The Alta HR ticks all of those boxes. With a similar look to the Charge 2, it’s considerably thinner. And it’s not far off the previous champion of lightweight wearables – the Jawbone UP3.

And like the Charge 2, it also looks great on the wrist. Many devices look a bit ugly, are too bulky or worse still, both. And that doesn’t inspire long-term use. But I thought I’d be happy keeping the slim and sleek Alta HR on for a month, and I was right.

Another key point is that it has a fantastic battery life – one week with a single charge. And that means less risk of not using it because you can’t find the charging cable or you forget to put it back on again!

photo of the alta HR and jawbone uP 3 both on my wrist
The Alta HR compared to the lightweight Jawbone Up 3

First tests – basic accuracy

The sleep stage breakdown is largely possible because of the ability to combine data from both the movement and constant heart rate sensors. So to trust the sleep data, it would be helpful if the movement and heart rate appear accurate during the daytime too.

Where heart rate is concerned, the resting heart rate appears very accurate. I tested it against my pulse and stopwatch many times during the month, and it was pretty much always spot on.

When it came to heavy exercise, however, it was a whole other story. The Alta really struggles to keep up when I’m at the gym – possibly because of the constant wrist bending when lifting weights and rowing, which Fitbit themselves admit can cause problems.

But during the night, that shouldn’t be an issue. So I’m reasonably satisfied that when I’m not moving, the heart rate reading can be trusted (as long as I don’t lie in an awkward position!).

As for less vigorous movement, again it seems pretty good. It counts my steps well during the day, and reacts automatically to exercise such as walking or cycling. And importantly, when I get up in the night to use the toilet or get a drink, it hasn’t missed it once (more on that later).

An important point here is that this is the kind of initial testing the average person might do with a new device. And if a device passes these tests, it’s more likely the owner will trust the more complex data like sleep stages.

Setting a sleep schedule and reminders to stick to it

One of the things I really liked during the month is the option to set a sleep goal / schedule and then get reminders to stick to it.

In the App settings, you can input your target sleep schedule. Since I’m a bit of a night owl, I went with bedtime at 12:30 a.m. and wake up at 8:30 a.m.

You can limit the days for your schedule if you like, but I know I personally benefit from a regular 7 day a week pattern.

Following that, you can ask for a reminder to help you wind down for sleep, which I set an hour before at 11:30 p.m.

Every night I then received both a notification on my phone and a vibrating reminder on my wrist to encourage me to stick to that bedtime. And in theory, start winding down by putting aside any late night work, and reading a book or relaxing rather than watching the next episode of my favorite TV series.

I found this a very helpful tool, and one which I can see actually benefiting people. And to help motivate you even more, if you manage to hit your target you’ll get a green star on the App the next morning.

So let’s take a look at the App data and how useful it might be.

App page 1 – the dashboard

fitbit app page 1 screenshot

The above screenshot shows the summary on the dashboard on the Fitbit phone App. It’s Monday morning and I’m working from home, so there’s not much activity logged as yet (wait till my gym session this afternoon!)

The important part, for now though, is the sleep section. It shows 8 hours 12 minutes total sleep time and 69 minutes awake during the night. I did have a bit of a restless night, so that makes sense.

To find out more about my sleep, you then click on the sleep section to get more detail.

App page 2 – a closer look at my total sleep

screenshot of my fitbit app sleep data for the last week

The second page of the App shows you two main things: a visual representation of how much total sleep you had in the last week on top.

And below there’s a scrollable list of all your previous night’s sleep – mine goes back over a year, even registering my Charge 2 and Blaze data.

What’s immediately clear is that I got a green star last night for hitting my personal total asleep goal of 7 hr 30 min. Great!

I can also see that it’s only the second time I’ve hit it in the past week, falling behind on the other 5 days. Not so great, so perhaps I need to think about why that is and pay more attention to my sleep schedule.

App page 2 continued…

screenshot showing the fitbit app previous week

When I scroll further down the main sleep page on the App, I can see some problems with the past week. For one, I’m regularly going to sleep later than my target time of 12:30 a.m.

Secondly, I’m really not doing very well at waking up at the same time and getting out of bed! My wake up time has a 2 hour range, and something I really need to improve.

The good news is that I did actually got to bed much earlier than the times recorded, but was just in bed reading. The fact that it hasn’t recorded that as sleep is very important, and a relief to see.

Capturing a bad night’s sleep

An interesting point in this last week though is what happened on Friday. I was ill that night and slept badly. I took the morning off, and tried to get some more sleep to recover. And the Fitbit was very accurate in recording those 2 separate phases of sleep.

It doesn’t record stages if the sleep is less than 3 hours, so the 1 hr 37 min sleep is just a total time. Nevertheless, I was impressed that it picked up the total time for both phases.

I do think the first phase is a bit inaccurate, however, as I felt like I slept less and was awake in bed resting. A classic sleep tracker problem which unfortunately still crops up from time to time. But it still highlights well the general idea that it was a bad night’s sleep.

Overall, I like the way you can see the total sleep time for each day, an average for each week and stars for when you hit your sleep goal. It looks good visually, is easy to read and understand. And the patterns make you think about how well you’re meeting your goal or not.

App page 3 – the sleep stages

fitbit app sleep stages

When you click on any of the days in the previous page, you’ll find the sleep stages for that night. This is where you start to see your sleep in more detail, and also potentially get a little confused. So it’s interesting to see how Fitbit decided to present the data.

First of all you can see your stages all together, presented in a pretty chart. Even though there are technically more stages, Fitbit chooses to group them into awake, REM, light and deep.

Unless you have a good understanding of the science behind sleep stages, the chart is kind of meaningless though. So it’s good to see the total for each stage broken down into times and percentages below.

But what does 49% of the time spent in Light sleep mean though? Is 1 hr 50 min of deep sleep the right amount or do I have a sleep disorder? These are the kind of questions I wanted to see answers to, as I imagine most people would.

And to get some answers, it seems you have to look in 3 different places.

Information about each stage

deep sleep stage screenshot

When you click on the main sleep stage graph, you can access 4 more pages – one for each of the stages. That way you can visually see when you were in that stage during the night, as well as the exact times (if you click the bars). And underneath are a couple of key notes about that stage.

In the above screenshot, I’m told I was in deep sleep for 19% of the night. I did wake up feeling refreshed, so going by the key notes, logically I can assume 19% might be a solid time.

But that’s assuming the total time was enough that 19% of that total time can be considered solid. More on that point later.

The notes are brief, but all useful. I like that you’re told it’s typical to wake 10-30 times per night. That’s a helpful bit of information that might stop you feeling anxious about your sleep data.

And it’s good you’re told REM sleep typically occurs later in the night. Again, that might stop you worrying when you realize it’s missing from the first part of the night.

Benchmark against your gender and age

fitbit app benchmark data screenshot

The screenshot above shows perhaps my favorite part of the new Fitbit sleep tracking data: the benchmark against people your age and gender, and also against your own 30 day average.

Assuming it’s accurate, to me this is a fantastic way to help people feel less anxious about their sleep. And of course, it’s actually telling you something useful about the sleep stages, rather than just leaving you to work out what all those graphs mean.

For last night’s sleep, the App tells me that my sleep is surprisingly average for men my age. I’m almost exactly in the middle for awake, REM and light. And I even got more than average deep sleep, which is the stage that leaves you feeling refreshed.

So going by these results, I might assume I have nothing to complain about. But before I start editing my status as an insomniac, there’s a small caveat.

These are benchmarks regarding percentage time in each stage. They don’t take into account whether you actually slept for long enough for those percentages to be enough in total.

At the end of the day, how you actually feel in the morning will still tell you more about whether you got enough sleep than graphs, percentages and benchmarks on an App.

That’s not to take away from the potential usefulness of the comparison though. If you regularly get much more or less of a sleep stage than the average person, it might be a good idea to mention it to your doctor to see if they think it needs to be looked into.

More information about sleep stages

I mentioned that there were 3 sources of answers about the meaning of your sleep stages. We’ve seen the individual breakdowns and key notes, and also the benchmarks.

The third is the Fitbit sleep tracking page on their website, which you’re taken to if you click ‘learn more’, which appears next to the sleep stages. There you’ll find further clarification of the sleep stages, though it still doesn’t clarify points like how much time in deep sleep could be considered ‘solid’.

I think that’s partly because we’re all different, and our sleep will vary from one night to the next naturally. So again, the importance of knowing how much sleep you need to be at your best can’t be understated.

Once you know how much total sleep you need to feel good, you can enter that as your sleep goal. Then hopefully the sleep stages will fall into the average range in the long-term, helping you feel good about your sleep pattern and motivated to stick to a good sleep schedule.

Sleep insights / coaching

Either my sleep is better than I thought, or I just haven’t worn the Alta HR for long enough yet, because I haven’t received any useful sleep insights so far. I know they will eventually come as the device gets to know me better, so hopefully by the next article I’ll have some to discuss.

What I did receive though is a couple of emails reminding me of all the different sleep features I can and should be making use of. I like that Fitbit follow you up this way, gently motivating you to do important things like set sleep goals and reminders.

Update note: for some reason, the insights never arrived when I had the Alta HR. But they do now with my Versa, even though they are general and would only be personalized if you go premium.

How accurate was the Alta HR overall?

Overall sleep and wakings

I kept a close eye on the things I could objectively record over the month. On most days, I was happy with the falling asleep time and waking time. However, there were 3 days when I felt it was off by more than 5-10 minutes and so changed the data manually.

On the day I was ill, I deleted 40 mins sleep when I was definitely awake in the night and not moving much. And on two other days I deleted 20 in the morning when I woke up and stayed in bed, unable to fall asleep again.

Impressively, there were no mistakes when I got up to use the bathroom or get a drink from the kitchen.

So I think there were 3 days in the month where the accuracy was off by enough for me to feel the need to adjust it manually. Personally, I’m quite happy with that as it’s not as bad as many other sleep trackers, and it’s accurate enough for me to feel like it’s useful.

Sleep stages

photo of my phone with the fitbit sleep app on the screen

The problem with judging the accuracy of the sleep stages is that, well, you can’t. Not unless you wear the device in a sleep center and compare it to a polysomnogram.

To a certain extent you can use the benchmark with your past 30 days and other people, combined with how you feel, to get a very rough idea of the accuracy. But really, you’re left to trust the claims of the manufacturer where accuracy is concerned.

Fitbit have never claimed to be 100% accurate, using words like ‘estimate’ carefully. But in April 2017, some interesting research was published in the journal sleep, in which wearables were in fact compared with proper sleep lab tests.

The researchers apparently demonstrated that wearable devices which track both movement and heart rate are more accurate than previously, concluding:

These results suggest that a wrist worn device with movement and cardiac sensors can be used to determine sleep stages with a reasonable degree of accuracy in normal adult sleepers, but without the cost and artificial sleep environment of a sleep laboratory. The reported performance figures are similar or better than previously reported results from non-EEG based sleep staging using combinations of cardiac, respiratory and movement information.

This research was supported by Fitbit (make your own judgment on that!). But it does suggest home sleep trackers might be entering a new era where reliability is concerned.


Personally, I like Fitbit’s new and improved sleep tracking. Even though it’s impossible to say just how accurate it really is yourself, it does seem more accurate than it used to be at least.

A year ago, my Blaze and Charge 2 sometimes added up to an extra hour to my sleep if I was awake and motionless. And although there were a few mistakes during the past month, there was nothing that wildly inaccurate.

I’ve found the sleep goal setting very useful, even if I’m struggling to meet it. But it’s constantly on my mind now, so I’ll be trying to get more of those green stars!

I like the idea of the sleep stage benchmarks. Again, I can’t be sure if it’s completely accurate, but I can be sure it makes me feel better about my sleep. I almost always fall under the ‘normal range’ for men my age, and even though I take it with a pinch of salt, it’s still kind of a relief to know.

As for the Alta HR, this wasn’t meant to be a review of the device itself. But I should end by saying it’s grown on me over the weeks. It’s like the smaller sibling of the Charge 2, and although I first missed the mindfulness App and the more accurate exercise tracking, I really like the thin design and great battery life.

You might also like

For more information about the accuracy and reliability of sleep trackers in general, you might like to read about the way sleep trackers work.

Your thoughts

If you use a Fitbit, how have you found the new sleep tracking so far? Which features do you find more or less useful? And does it seem accurate to you? Feel free to leave a comment below with your thoughts.


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  1. I first had a Fitbit Versa and now a Versa 2 and the situation is the same in both instances. My typical sleep times are from around 23:30 to about 06:30 or 07:00. Almost every night my Fitbit shows that I slept for an hour or two and then that I only slept again after about anything from one to three hours later. It does not show it as awake time, but as two separate sleep sessions. In most cases I am not aware of being awake during that time at all and therefor doubt it it is true. Do you have any explanation for this?

    • Hi Willie
      That seems strange to me. Have you tried adjusting the sensitivity setting to see if that makes a difference?

    • Hi Amy
      Yes, but I have so far refused to get excited about using Apple watches for sleep tracking purely because of the battery life. I usually stick with wrist based devices that last for several days, or dedicated sleep trackers that are constantly plugged in. There are admittedly some new devices which are pretty good, and also have a bad battery life and need to be charged every day, so Apple aren’t the only company that struggle with this issue. But I personally find it kind of annoying when you lose data because it switches off in the middle of the night. I also know that it’s very easy to ‘forget’ that your device is charging and put it on again.

      • Hi Joanne
        Unfortunately, sleep trackers do make mistakes. So it might be that. But sometimes they also show much less total sleep if their were lots of wakings in the night. I’d check the graphs to see if it has recorded lots of wakings.

  2. Hello!
    I started using the Alta HR over a year ago because I wanted to track the sleep stages. I appreciate your review, however I don’t see you or others addressing the problem I have found.

    Because I figured out how to update the sleep record as needed, for example when it was inaccurate about when I woke up, I have now noticed that it changes what it has recorded about the stages when one updates it.

    Specifically, one night recently it recorded my sleep in two distinct logs separated from one another because I was awake for a while. I wanted to have one log for the night, so I deleted one and gave the other the beginning and end of the night’s sleep. I looked at the two before combining them, so I know that it showed deep sleep at around 4 AM for at least 40 minutes. When I combined the two, which is easy, it eliminated that period of deep sleep. The new single log showed only one period of deep sleep at about midnight.
    I’ve seen this happen multiple times. Fitbit appears to be relatively accurate in tracking things it monitors directly, like steps and heart rate. However, the sleep stages use an algorithm and do not directly track sleep stages. The way Fitbit does this, if you change the time you went to sleep and/or the time you wake up, you are likely to see significant changes in what it tells you about how much you were in each stage.

    Given this, I don’t see how to have confidence that what it says about deep sleep or REM sleep is accurate. Since small changes in when one went to sleep or awakened can entirely remove a period of deep sleep or change it’s length significantly, how can we believe that it is accurate? I look forward to hearing your perspective on this question.


    • Hi Lou

      Thanks for your comment. My perspective is that I agree with you! Unfortunately, it’s examples like this that cast doubt on sleep trackers and their ability to measure sleep stages. As you rightly say, they don’t actually measure sleep stages directly, but use an algorithm to estimate them. So when you manually change a key part of the data that they use to form that estimation, it has a knock-on effect.
      This is why I say throughout my blog to take sleep stage tracking with a pinch of salt. Or perhaps in some cases, with a whole bag of salt.

      • Ya I started getting really focused on sleeping in the past month after watching Joe Rogan podcast with Matthew Walker ( sleep specialist) I have tried increasing my sleep time from a total of 8 hrs a night to 9 but the charge 2 is saying the only thing I have increased is light sleep or my awake time. Last night I slept almost 10 hrs and Still couldn’t get 2 hrs of deep or REM something isn’t right

  3. Thank you Ethan for a great article. I have not had such accuracy from my Charge 2. For example, I went to bed at 9:30 on Wednesday and fell asleep immediately. The following morning, my dash told me I had gone to bed at 12:30 and slept only 5.5 hours. I hardly ever see stages of deep sleep, which concerns me a lot since lack of deep sleep is linked to Alzheimer’s. I have had my tracker and it’s predecessor for over six years. I just ordered an Oura in the hope that it may be more accurate. I have tried wearing my Fitbit on both wrists (at separate times haha) loosely and fairly tight. It makes no difference.

    • Hi Antonia
      Thanks for your comment and kind compliment. It’s a shame the Charge 2 hasn’t worked out for you. Let me know if the Oura is more accurate for you.

  4. Thanks for the great article. For some reason I had missed the benchmark info so that has helped me. I see that in comparison to others my age, I’m pretty average and better in 2 categories. This has been reassuring.

    • Hi Cheryl
      You’re welcome – it’s always good to know an article was useful. I really like the benchmark part, even though I’m not always sure exactly how useful it is beyond being reassuring if you’re the same as everyone else. I guess the issue is what do you do if you’re not the same?

  5. Hi Ethan, My fitbit alta takes a long time to show the amount of sleep I have had the previous night. The data is shown only a day after ie after say 20 to 24 hrs.

    • Hi Shavi
      I have had a similar issue when crossing a time zone and not setting the clock properly, so it is 12 hours out. Could it be that? If not, have you updated the firmware? Have you changed wifi or don’t have bluetooth working properly on your phone? These are all issues that can mess with the uploading of data. If none of those help, I’d get in touch with Fitbit customer services to find out what they suggest.

    • My Alta Fitbit says I am asleep when I am awake.
      I know when I turnover, and I do it often on purpose and I know I am not asleep.
      Also, I often read while in bed and my Fitbit tells me I am sleeping.
      What to do?

  6. This was a great article. I have used Fitbit for years starting with One, Charge 2 and now Versa. I completely agree with you on the sleep data. Versa seems very accurate (Charge was not, many manual adjustments prior to 2017). Any reason you did not include the Versa in your discussion? Thanks,

    • Hi Alison
      Thanks for your comment. The Versa hadn’t come out when I first wrote the article. I actually wrote another article more recently with a comparison of different sleep trackers you might find interesting. The Versa is one of the ones in that test, and came out very well on the whole.

  7. My Fitbit Charge shows 1 hour less than I actually sleep. I aim for 7 hours + each night if possible.

    Last night it showed 6 hr 4 min / 47 min awake.

    I slept from 23.56-06.48 according to my watch which is accurate – this is close to hitting my target of 7 hours.

    So my questions are:
    Does the Fitbit subtract the time awake from your sleep time?
    And what is this time awake – when you roll over?

    Thanks for your help

    • Hi Sarah
      Thanks for your comment. I believe it does subtract wake time. How it calculates the exact algorithm I don’t know. I’m not sure if it calls rolling over as awake, but perhaps more movement combined with a particular heart rate at the time of the movement. You can also change the sensitivity of the sleep tracking, which is sometimes worth experimenting with if you think it’s being over-zealous with the calculation of how often and for how long you roll over/wake up.

          • Thank you!!! What a great article. It cleared up a lot of questions and needless anxiety for me. I love my Fitbit Alta Hr. Thanks for mentioning the ‘I know I wasn’t really asleep, but lying still ‘ theory.

          • Hi Laira
            You’re very welcome – it’s always good to know an article is appreciated.

          • Device: Alta HR

            Concerns: I’m getting plenty of sleep and waking up feeling refreshed – but the tracker is showing consistently between 2min and 20min of REM sleep each night. Even on nights when I remember extensive dreams, which should indicate a decent amount of REM, it’s only reporting a tiny fraction of what I should be getting. The net result is that when I check the app in the morning, I’m disappointed and feel like the sleep wasn’t restful. Has anyone else noticed and under-tracking of REM time? Or do you think I’m actually getting less than 20m each night which is incredibly unhealthy and I should be concerned?

          • Hi Zachary
            Thanks for your comment. Personally, I would take the sleep stage results with a pinch of salt. If you wake up feeling refreshed, and don’t feel tired or have other symptoms of sleep deprivation during the day, that is the best indicator of good sleep really. If you have any issues, then perhaps you could ask your doctor about your sleep and talk about your tracker data. But if you feel fine, I would probably assume the tracking isn’t right rather than start worrying that something is seriously wrong.

          • My Charge 2 has stopped recording sleep states. I keep trying to adjust my watch but it doesn’t work.
            Up until a month ago, I was able to record the states. Do I just need a new watch?

          • Hi Ernie
            Have you tried contacting Fitbit to see if they can help if the warranty is still active?

    • Hi Melanie
      If you go into the Fitbit App and click on resting bpm. Then click the day you’re interested in and a graph will appear. Click that graph to make it larger, and then you can click on a different point in the graph to see what the bpm was at specific times in the night.
      It’s a bit of a fiddly aspect of the tracking to access, but it’s the only way I know of to get the heart rate in the night. I don’t think there is an option to find out the average bpm for just when you were sleeping though. You either get all day, or pinpoint times that you choose on the graph.

  8. I just got a Fitbit Alta hr but my sleep log doesn’t look like yours.
    It doesn’t show the stages
    It looks just like my old Fitbit Alta that was not a HR

    • Hi Nancy
      That’s strange. Even if you tap the sleep screen and scroll through different sections? Sometimes it’s confusing trying to find the right data on the App – whenever I get a new tracker and App, I spend time tapping everything to see what opens up new menus or sections. But if you still can’t find it, I’d get in touch with Fitbit to find out what is happening.

  9. I came across your website (which I look forward to investigating further) when I Googled Fitbit Charge 2 and sleep. I’ve been wearing a Flex for the last couple of years and recently changed over to the Charge 2. Flex always showed a difference between the time lights went out and when I woke up, but with the Charge 2 it’s been even more pronounced. There have been several nights when there’s been no sleep recorded at all. Last night was one of them. The night before I was in bed for 11 1/2 hours and Fitbit said I had 5 1/2. The night before, Fitbit said I was awake for 2 hours between 5:00 AM and 7:00 AM. I know I have to go to a sleep lab and get this investigated, but I wanted to let you know how helpful I found it to read your very detailed report on your experience and on the accuracy of your device.

    • Hi Bill
      Thanks for your comment, and it’s good to know you found the site helpful so far. That does sound strange. If it recorded no sleep at all, and you know you were definitely asleep, then there’s an issue with the Fitbit. And do you remember feeling awake for those 2 hours? I think it’s important to also take into account how we feel and what we remember when looking through sleep tracker data. They aren’t 100% accurate, so it’s good to compare notes with your own recollection!

      • Thanks! I think the problem may be in the way it is measuring my heart rate. I did speak to them today and changed the way of measuring from “auto” (which saves memory when I’m not wearing it) to “on” (as in all the time). I noticed that the heart rate monitor was showing results that were classified as “fat burning” while I was asleep, which may indicate to Fitbit that I’m awake. No, I’m not aware that I’m awake.

        • Hi again Bill
          You’re welcome! Yes, that doesn’t sound good at all – unless you did a huge amount of exercise before going to bed and your heart rate was still elevated, which seems unlikely.

  10. Ethan,
    You said you had years of insomnia. what do you mean by that? whatever recording you have shown indicates that you seem to sleep pretty well now.
    My question is, I am 71 and suffering from insomnia for 4 years. drugs are there but I have avoided. I don’t have any apparent physical issue except that I take antihypertensive drugs. otherwise, walk 6km a day a day and 3 times a week yoga. very active otherwise.
    These gadgets will only tell you how bad or good you were last night.
    If you have something to share, let me know.

    • Hi Rngarajan
      Thanks for your comment. I have had insomnia for a long time, but it comes in waves, and sometimes I actually sleep very well. At the time of writing this article, my sleep wasn’t too bad – as you rightly point out.
      In terms of your question, it’s impossible for me to guess what might be affecting your sleep. When you say you have insomnia, what do you mean exactly? How much sleep do you get on average?

  11. Hi Ethan,
    I noticed on your article about the best sleep trackers for 2018 that the FitBit Blaze is omitted. I realize that the Ionic is more advanced, but it is also an additional $100. I am just wondering if there is any particular reason for the omission?
    Thanks for sharing your insights!

    • Hi Jenn
      Thanks for your comment. I actually had the Blaze in the review for a long time, but decided to replace it for a few reasons. Firstly, because when featuring so many Fitbits, perhaps in a way that some people will see as biased, I thought I should at least focus more on the latest ones. Secondly, because I personally prefer the Ionic to the Blaze, and much more so. I know it’s more expensive, but in my opinion, it’s also a lot better, and worth the additional cost. I think for people who want to spend less, the Alta or Charge 2 are good options. But the Blaze is still a viable choice too, if you like that style, but the Ionic is too expensive.

      • Hi Ethan,
        Thanks for your thoughtful reply. I was excited to see in my inbox today an email about the upcoming release of the Fitbit Versa! Looks like the price point and closer to the design of the Blaze, but closer to the features of the Ionic (and more lightweight than either!) I’d love to know if you get a chance to preview it!
        Thanks again,

        • Hi Jenn
          No problem! Yes, I’m looking forward to seeing what it has to offer. The lower price and the rounded design I can see appealing to many people. I’ll have a good test of it later in the year.