Scientific Sleep Test : Oura, Fitbit/Google, Mi Band (More💰 = Better?)

[@TheQuantifiedScientist]

🔴 Max's blog: blog.kto.to/oura-v3-vs-eeg-home-sleep-lab-test 🔴 General Amazon link*: geni.us/thequantifiedscientist 🔴 Oura Link*: ouraring.sjv.io/rQ4L33 🟢 Instagram: instagram.com/quantified_scientist/ 🟠 Shorts: www.youtube.com/@smartwatchshorts 🔵 Newsletter: www.robterhorst.com 🟡 Twitter: @QuantifiedRob * Affiliate (paid) links support the channel by earning me a commission on any sale, and it doesn't cost you any more! My opinions are completely my own, and this content is not sponsored. ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ 👇 At least $30 off any new WHOOP membership, affiliate* (paid) link, supports the channel!👇 join.whoop.com/QuantifiedScientist ($30 off any new WHOOP membership) ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ 👇Amazon Affiliate* (paid) links. Supports the channel, doesn't cost you any more!👇 ▬▬▬▬▬▬▬▬▬▬BEST WATCHES▬▬▬▬▬▬▬▬▬▬ 🔴 Eight sleep discount*: eight-sleep.ioym.net/TheQuantifiedScientist + add code “TQS” for total discount 🔴 Whoop Strap 4.0 discount*: join.whoop.com/QuantifiedScientist 🔴 Oura Link*: ouraring.sjv.io/rQ4L33 🔴 General Amazon link*: geni.us/thequantifiedscientist 🔴 Polar H10: geni.us/hnXc ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬

[@ikOldBoy]

Hello Sir, One area you may want to look into is Steps counting. A somewhat 'small' but equally important area, I genuinely feel you should try Test. Test all the different smart watches and see the most accurate when it comes to STEPS COUNTING.

[@zebseb03]

Can you do a review of the new Samsung fit3 ?

[@cyberfunk3793]

Would be interesting to see how the "Sleep as Android" app with H10 does compared against the Sleep2 App (previously known as Nukkuaa)

[@tomoprime217]

where is your friends Oura review link as promised?

[@siiddrb]

I love the concept behind Oura, but the subscription model makes me not want to get one. I instead opted for Ultrahuman Ring Air. Could you please test that device?

[@Cecilia-e6i]

I chose RingConn smart ring and also wanted to see comparisons between different smart rings:)

[@HenrikAaenMortensen]

I would also like do se a Ring comparison.

[@zohandvir9606]

A lot of people say its very inaccurate ...

[@danneal2792]

You have done a ton of work on stage accuracy. Have you ever thought about doing a review on the apps behind the devices? Which app gives the best sleep scores? Each app has its own way to score your sleep. Which app gives the best metric for sleep health, how would you quantify it?

[@thebeatles9]

stage precision*

[@MEODOWLA]

He described NUKKUAA app. But it's not available in all regions.

[@MorriganJade]

Yeah, I'm quite curious for example for the Sleep As Android app. Since I have my Mi Band 5 connected to it. And in comparison to the Notify & Fitness app, or the official app combined with the third party support tool for SAA, I have a feeling that Sleep As Android is an amazing bang for the buck in terms of "better accuracy than what's provided".

[@jkuzel]

exactly, hardware is one thing, and i get hes about the hardware and sensors and that can be evaluated sort of objectivelly .. but i would be way more interested in subjective review of all the major apps of the popular devices ... how useful they actually are to help with sleep quality

[@jazzcobber]

Yes please! Iwould alsom very much appreciate commentary on most useful app por practical feedback. @TheQuantifiedScientist

[@Vital_form]

I would really love a video on the best non-subscription based product. I dont know how other people feel but paying a subscription for a product I already bought is a bit of a wrought.

[@MrAnonimR]

This is really a 2-way street. On one side you already bought the product and you paid the cost of developing that hardware and some profit. On the other side, if that product has an app that regularly receives updates, there are some other developing costs implied. I would be ready to pay maybe 1-2$ a month for such an app, but not more than 3$ a month. Only if the app receives regular updates and improvements

[@tomoprime217]

@@MrAnonimR agreed $6 for the year makes better sense to keep an app up to date.

[@TripleIProductions]

I bought an apple watch S9 because of your results for better sleep tracking and HR monitoring. I used to have a mi band 7 before.

[@TheQuantifiedScientist]

Hope you like it!

[@TripleIProductions]

It's amazing! Couldn't have bought a better watch, and I use it for both all the time. Thank you for your tests! @@TheQuantifiedScientist

[@ikOldBoy]

Mí Band 7? Hahaha

[@TripleIProductions]

It was an amazing watch. 12 days of battery life, and cheap af! Could do 80% of everything my applewatch can do as well for 20X cheaper price. @@ikOldBoy

[@Yorumcu666]

@@ikOldBoy what are u laughing for? One of them is £400 the other one is £30.

[@MartinSchuchert]

Thanks!

[@startingtoday4663]

My oura ring stopped working after 1 year and 2 months. Warranty only covered 1 year.

[@thebeatles9]

buy a new one (same model) and return the old one with the new receipt.

[@martinklein2201]

As a bad insomniac until now I have used miband 6 and 7 for sleep tracking and sleep tracking is after "how I subjectively feel in mornings" 2nd most important factor if I should go to work or not. I am happy I found your YT channel because you put real effort in your videos (as I would if I had YT channel :) ) and I ordered Oura 3 and I am sure it will pay off with better sleep data. Thank you

[@beatrizmoraes2310]

Samee

[@T0M3R07]

Hello Rob/@TheQuantifiedScientist, do you have any updates regarding the UltraHuman ring, please? I remember you mentioned an ongoing testing in one of the previous video comment section, and would love to hear possible results. Thanks!

[@TheQuantifiedScientist]

They should provide me with some of the data in a format I can use soon :-)

[@T0M3R07]

@@TheQuantifiedScientist That's great to hear. I'm looking forward to that moment. :)

[@GadgetyMV]

Great to see this correlation between your work and the scientific study! The product development during the past year that has caught my eye the most was the Pixel Watch 2 with Fitbit integration and the improvement that brought. This because I'm on Wear OS for other reasons than pure sleep tracking. For this reason I also note that the Galaxy Watch 5 Pro scored pretty well in your testing, but not the rest of the Samsung range, which is both unfortunate and odd. In the end rather than all the nightly metrics and trend tracking basic advice on how to improve sleep quality probably does the most good. It is also a lot less in terms of financial outlay. If one is unable to apply that advice all the measurements in the world won't help.

[@theAwakenedOne007]

hi. I received a Pixel watch 2 for Christmas and returned it a couple weeks ago. it was nice and a quality build. but, the "watch" app is terrible. the Bluetooth connection cancels out my Android auto connection to my car making it unconnectable. and currently, there aren't any sync options available for your phone alarms to work with the Pixel Watch 2. I currently have a Galaxy S22+. I read so many forums to get these to work and currently, there aren't any fixes. the Fitbit app free is fine I guess. I had a Fitbit Inspire a while back so I am familiar with the free and premium Fitbit app usage. In all, I was really excited to get it. but after a couple weeks, I was just disappointed. I just wanted to give my experience with it because I researched a lot before getting this. And, for the money, it currently isn't worth it in my opinion.

[@novizxc]

Where is the link to the blog post?

[@TheQuantifiedScientist]

Good point! Totally forgot when writing the description, will add it in the pinned comment... Here it is: blog.kto.to/oura-v3-vs-eeg-home-sleep-lab-test

[@StephenBieda]

Rob are you planning to test the new RingConn? Also, what is the best device for tracking snoring and sleep apnea?

[@SofieWright]

Have you tested other rings? Would love to see a comparison of the ultra human and the ringconn rings too

[@coder_rc]

Thank you for these videos

[@TheQuantifiedScientist]

Glad you like them!

[@youngsuk3329]

Bought a 2nd hand fitbit inspire 2 for 20 bucks, best decision ever, tks so much for the videos and tests 😊😊

[@kendrazoa958]

can i hire you to consult on unique needs for sleep track? disabled with multiple rare conditions, including rare circadian rhythm disorder (sighted Non-24-hour sleep-wake disorder), that cause extreme sleep disruptions.

[@olivern4784]

You have a peer reviewed validation of your sleep testing!

[@TheQuantifiedScientist]

Great point!

[@fidrewe99]

Since sleep tracking does not only depend on the device, but the software used is equally important, it would be really interesting to see tests of the sleep tracking performance of various apps (e.g. Pillow) on a high quality smart watch like an apple watch 9.

[@petrino]

why havent anyone made a sleep tracker earplug? thats the only thing I can think of wearing that wont affect my sleep negatively :P

[@TheQuantifiedScientist]

There are EEG earplugs. I'll be testing some soon :-)

[@neilcameron434]

I believe the soundcore sleep A10 track sleep, no idea how accurate.

[@vedransimic86]

@@TheQuantifiedScientist Flowtime Brain Tag. Are there more others?

[@brianquigley5743]

@@TheQuantifiedScientistI'll be interested in practical matters like: 1) how do you keep earplugs inwhile you sleep. 2) battery life. EDIT: ZDNet has an interesting, but non-scieintific review of the A10 buds.

[@HereSoley]

Will you review other rings like UltraHuman and RingConn and maybe also compare these to Oura? The rings market is growing and seems very interesting to me!

[@Cloudnine2024]

Can you test the Ultrahuman Air Ring please?

[@chibonchibon3967]

thanks, great test as usual, I learn a lot and decide to save money to buy better and expensive device that works!

[@TheQuantifiedScientist]

Glad to help!

[@mhmdabdelrazek8568]

Bud you made a test before for mi band 7 and it was very good in tracking deep sleep so what happened ???

[@Cuffers93]

One thing that's worth mentioning with the whoop is that it may well be different on the bicep band than on the wrist as for me it's always been more accurate like that and it has been shown to be more accurate at HR readings too, especially during exercise. It would be interesting to see where it would land on the chart if you used it like that instead!

[@veganpotterthevegan]

My whoop was often 30-50bpm off during workouts, it also made up naps I never took. If the arm band were 50% better, I'd still be very unhappy😂 They sent me a replacement unit that was just as bad

[@Cuffers93]

@@veganpotterthevegan It has registered me being asleep when I've not been but that's not so surprising when you're still at times and you can easily delete it so I don't mind that so much. I happened to get a free bicep band when I sent them my heart rate data being way off and too low in one of my workouts... using the bicep band now means the average hr across any workout is 2bpm lower than my apple watch or polar h10 - if you still have your whoop it's worth seeing if that's still an option!

[@veganpotterthevegan]

@Cuffers93 they offered it to me but I know I'd hate wearing an arm band. But the fact that it makes up naps makes me not believe the sleep data I was getting either. I was really hoping it would also replace my HR chest strap but no way😅 My Garmin Vivosmart 5 is much closer. It's still 5-10bpm off but it doesn't make up naps or workouts. The whoop is inexcusably inaccurate for how expensive it is. I'd happily pay double if I could trust the data though

[@Cuffers93]

@@veganpotterthevegan ahh okay. Well I’ve found it to be more accurate for sleep too on the arm - closer to the Apple Watch. I do hope they fix it for the 5.0 whenever they release it though, although I have my doubts. The bicep band actually isn’t as bad as you may think, but does take a bit of getting used to and the right fit as well.

[@veganpotterthevegan]

@Cuffers93 oh, I'm sure it would be more accurate on the arm. I still think it would be very inaccurate though.... just an improvement. *I don't want the band due to the heat. I wear the thinnest gear possible to keep cool in dessert heat(I live in Utah). I regularly do 4-6hr bike rides in the summer, even if it's 110 degrees.

[@ms11-p4m]

Why did the position of the google pixel watch 2 change compared to your last video? Also, is there a difference between 2 and 1 when it comes to sleep tracking?

[@TheQuantifiedScientist]

Hi! I already added more data. My guess is there are no big differences, but I need to retest this still

[@ms11-p4m]

Thanks! :) @@TheQuantifiedScientist

[@tonysako]

will you be testing ringconn? im waiting so much for this

[@sashabrown6865]

Thank you for sharing this information it has helped me decide what device to use and purchase in the future!

[@emeraldzen]

Do you have plans to test the Oura ring 4?

[@voodooparadox2513]

Please share a test about the EEG device Muse S Gen 2…

[@stefanmisic7405]

Why was google pixel watch 2 moved from the high end position? We never saw the reason why. In one video watch was at the high position and all of sudden moved back...hopefully this doesnt impact you credibility in this field but you should explain why it happened anyway.

[@gaboqv]

Seems he did more measuments, although it would be useful if this graph was online and with changelogs

[@wschozo]

Can you please review Muse S?? That seems to be the most consumer-friendly EEG device for sleep.

[@Tiamo1519]

Hey rob! Do you consider testing the Scanwatch 2?

[@frkvld]

In every video there is praise and advertising of the Oura ring, it seems like that you get a percentage from them for subscription payments

[@gracxx162]

we have some new plaers on the market for example ultrahuman will u test them?greetings

[@mello1016]

Pixel 2 has been forgotten?

[@bogdanpeicu6391]

Very good video! Can you test the accuracy of the CMF Watch pro by Nothing?

[@TheQuantifiedScientist]

Yes, soon 😊

[@nikolaussoundso]

Your general amazon links forwards me to the amazon main page

[@TheQuantifiedScientist]

Yes, that's correct. Anything you buy using that link should support the channel :-)

[@theaimuse]

What a fantastic approach. Some proper data. Question on the FitBit. Which one is it? The series has a long list of devices. Trying to find best value purchase for myself.

[@davidmarkleach]

So I just found this guy 15 minutes ago. Still can’t find an answer on what the Best Buy is for sleep tracking in the Fitbit line. Website has no affiliate links???????

[@mohamedel-shazly4940]

Thank you for the video. What is the best sleep tracker for 600 US $ for Android users. I do not want to pay subscription.

[@anybody3053]

could you do a comparison of smart rings ( oura, ultrahuman and ringcoon ) ?

[@Der_Richiee]

Anyone knows a way to wear a garmin Forerunner as an armband around the biceps/triceps like the wahoo band instead of around the wrist? I'm not allowed due to work.

[@federicopaez7256]

Hi, thanks for sharing. Do yo have plans to test ultrahuman ring?

[@ebohutomo]

Hi rob. Can you please review all the heart rete monitor chesttrap from lowest to highest budget?

[@gilrose12345]

Any chance to review Masimo W1 Sport?

[@CarmeloEstablier]

Hey man, do you think you'd be able to compare the Oura with other rings like the one from Ultrahuman? It'd be interesting to see how they compare.

[@TheMREREZ]

can i have link for fitbit inspire 3? or i can get it via your general link?

[@RadimSafran]

Hello, great video! Would you please consider "Oura Ring" Vs "Superhuman Ring Air" comparison? ♥

[@aaakmm1785]

It would be extremely interesting if you selected 2-3 watches and performed HR accuracy test on few different people to see how results differ. HR tests would not have to be as extensive as you do usually. Some everyday tasks, one run sessions may be enough to give a general idea of between subject variability.

[@AlexandrePopescu]

Hi, just discovered your channel, pretty amazing job you're doing! Have you heard about the Ultrahuman ring? Didn''t find any review of it.

[@drakewilliams_]

Is the Apple Watch SE under a different name on the graph? Or was it not tested?

[@olivern4784]

I am hoping the Pixel Watch 2 will begin to outperform the Fitbit devices over time. I am theorizing that the sleep algorithm will be optimized to reflect the data from the new multi-path heart rate sensor. PS Of course, my optimism may be misplaced due to the recent exodus of Fitbit employees from Google.

[@gauravthapa6060]

Same here

[@showyourtruth]

hi! can you do redmi watch 4?

[@wskbenz]

Hey Rob, steht ein Test der cmf watch pro auch auf deiner Liste?

[@rishiagrawal1151]

Hi, do you know if your fitbit findings here translate to the Charge 5? I noticed you used a different Fitbit model, so I wasn't sure. Thanks!

[@kelbinn]

I find that fitbit stop tracking if i wake up to feed my baby. Garmin/fitbit/apple continue my sleep.

[@yasserhussain4565]

Hi you need to find a smartwatch which will knock apple of the top of the list that should be your objective so plz find one

[@luc6732]

Are you planning to test the new mi band 8 pro global? How the score of HR 24h/7 in normal repouse use, and running.

[@den15423]

What is the Nukkuaa H10 device in your chart?

[@TheQuantifiedScientist]

It's an app called Nukkuaa that uses either the Polar H10 or Verity Sense :-)

[@den15423]

@@TheQuantifiedScientist Thanks!

[@jagannathishere]

@@TheQuantifiedScientist which is best location for verity sense - arm, wrist or temple?

[@supercobra888]

The Fitbit Charge 6 is not on the list?

[@QuantumBits0]

what about redmi watch 4?

[@OutsideGamer99]

Mega interessante Videos, gucke deine Tests sehr gern! Glaube ich fahre mit der AWU 1 ganz gut was das Datensammeln am Handgelenk betrifft. Könntest du wohl klarstellen was die grüne und blaue Färbungen bei der überdicht aller Geräte bedeutet? Ich nehme mal an nach einem Update. Beste Grüße aus Dortmund!

[@andpeo]

What about Ticwatch?

[@Liveinhk852]

any update of mi band 9

[@alexsalerno6018]

I have the AppleWatch 7, but i don't like the lack of suggestions on improving sleep. I think a better app could change everything. I don't understand how to interpret my sleep data with the apple watch...if you have any suggestions... I ordered the Oura ring. I waiting for the size kit

[@JayaLove]

Your reviews are amazing! Have you considered reviewing Ultrahuman Ring Air or Ringconn Ring? They are the two main Oura ring competitors.

[@The_Tiger-v8s]

My miband 7 worked ok, but now I am using Apple Watch 9 and it’s clearly bettter.

[@TheQuantifiedScientist]

Happy to hear that!

[@1989_golfmk2]

Can you do a comparisson with the ultrahuman ring? Thanks!

[@abdelwahabamloul3980]

could you please re update the data for the mi watch and add some testing for the redmi watch 4 , thanks abunch for this work , amazing as usualy very informative keep going

[@o114sthlm]

Wen Oura 4 test?

[@jackjhmc820]

I am still using mi band 5 and I think according to your old video it s actually more accurate than mi band 8, 7, 6?

[@Thundercloud1969]

Conclusion, no smart ring/watch etc. can compete with a PSG. I pass for now on a OURA ring or any other ring because simple said, if its really important for your health at some point in your life to track your sleep, you need something you can count on. (Petje af voor je video's Rob, fijn dat je er zoveel tijd insteekt)

[@castor4357]

Is a review on Suunto watches, especially the new Race, planned?

[@АтанасЦанков-л2ц]

Will you make review of Withnings scanwatch 2 and Lite ;]

[@danmaerra]

Hello thank you very much for your video it's helping a lot ! Why didn't test the withings scanwatch 2 ? I'm interested by this watch I really don't know if they're good or not 😬

[@taulantz]

What about Withings Scanwatch 2?

[@lukasmisko8906]

Hi, any plan for UltraHuman Ring Air testing?

[@yourbear2812]

What about mi band 8?

[@bederhajali]

Hello my friend, really looking forward to your view on the scan watch 2

[@luyzqint3760]

Hello, the new Huawei watch Fit 3 is out, are you going to tested?. Also, could you please test a budget watch, Spovan?.✌️

[@X_Mango12]

Hi Rob please can you please review the Redmi watch 4, I heard the heart rate tracking is amazing. Please confirm this. Thanks!

[@aidanbrennan7389]

Greet review. Greetings from Dundalk.

[@ferencschneider9652]

Can someone help me?🙂 How can you help the day after bad sleep?

[@usmanhaleem3964]

Listen to Matt walker’s podcast, he is the top sleep scientist in the country

[@gambitgambino1560]

can you please review gshock dwh5600

[@aaakmm1785]

Everyday life HR accuracy To get accurate HR during exercises everyone recommend chest straps. But what about outside of working out? How accurate is HR tracking during everyday life? e.g. sleeping, walking around the house, doing some chores, sitting in front of TV/computer, commuting to work, shopping, walking a dog, washing dishes, cleaning, just everyday life. Can I assume that during this 22-23 hours of everyday life even the basic optical sensor is decent enough? I don't know why but no one on youtube pays attention to that. Are they assuming HR accuracy for every day life is a solved problem and they focus only on working out accuracy?

[@marshallm.5397]

cant decide between Fitbit inspire 3 or Amazfit band 7. Amazfit is rated so poorly but it does have the new sensor so am wondering if that will be any better

[@bojantenja]

Boo, don't hope to much. Xiaomi had. A lot of years to fix some things,but they keep doing it with every new model.

[@brianquigley5743]

@@bojantenjaI stopped wearing an Amazfit within a few weeks because it was so erratic. I donated it to a thrift store and discovered later that their tech is based on stolen IP and they send your data to China.

[@Aditya-cd2lv]

Please make video on latest launched SAMSUNG GALAXY FIT 3 fitness band

[@jozefjozefovic786]

In one of you previous videos you compared H10 to ECG while doing different activities. You included activities as sitting and chores, would you recommend to buy H10 if I want to track my calories during the day? I assume that H10 would be the best for tracking calories. I'm not big fan of watches (during the workout) that's why I'm thinking of H10.

[@brianquigley5743]

I'm not Rob, but I can tell you about my own experience wearing a H10 with a Polar Unite watch at the same time... as well as a Fitbit Sense 2 and Samsung 4... the latter watches are reasonably accurate in indicating my heart rate compared to the H10/Unite combo. Using this device combo allows the Polar app to show you total calories burned AND fat, protein, and carbs burned as a percentage of the total. I have no way of knowing how accurate these numbers are... maybe it's something Rob could fifgure out...

[@gem2148]

Hey Rob, thank you for all the effort you put into those videos. Based on your reviews I've decided on Google pixel watch 2. I want something that can be an alternative to apple watches with best accuracy. I watched your Google pixel watch 2 scientific review and based my decision on it. Even though it's above my budget but I was able to save extra cash for it. So I still need some assurance from you to go ahead with my purchase. Do you still recommend it? Thank you so much 🙏

[@giuliaseoane168]

Pls test hawuei watch fit special edition

[@margeretheath597]

Can you compare various apple Apps and/to android sleep Apps please.

[@CrazyHunk14]

Please make a review of xiaomi watch 2 pro

[@georgesmith3022]

mi band if you are lying in bed watching tv after 12.00, it thinks you are sleeping

[@MyMd1111]

Dreem2 very good at measuring but very poor build quality! Had 3, all of them broke after 3-6 months. Dreem3 is not more availible for consumer as simple purchase.

[@NeoVdV]

Waiting g for a review of the Ringconn

[@vlad39738]

Sounds like that study tested on healthy people? What about people who actually have sleep problems?

[@fullofmysteries]

do you plan to also test the Xiaomi Watch 2 Pro? I just got it and I am curious about its accuracy.

[@FragEightyfive]

@19:50 get a bounty together and i am sure someone will spend the time to get it working.

[@Hdu3u3he83be]

Plz test the Ultrahuman ring

[@gammelgemse]

Isnt sleep tracking on smart watches a total scam? I mean you cant possibly infer something about your brainwaves just from heart rate data. These are physically completely different things. 🤔

[@hermannlodbrok8923]

One just needs to examine Participant ID 021 to conclude how worthless these devices are for those with insomnia and WASO and other sleep disorders. Sleep stages... so what? And spend 100s of $ for 75%...

[@gaboqv]

For some watches to achieve 95 accuracy I think there must be something going on

[@brianquigley1940]

So, basically, wrist watches are terrible at tracking sleep compared to PSG devices... which matches my experience wearing a Fitbit 2, Samsung 4, and Polar watch... and a Muse S and Dreem 2... The somnographs from the Muse and Dreem are consistent (albeit the Muse never shows my deep sleep, whereas the Dreem shows minimal activity, which aligns with my age).

[@TheQuantifiedScientist]

I wouldn't say wrist watches are all terrible, but without EEG/EOG information they are at a disadvantage for sure

[@brianquigley1940]

@TheQuantifiedScientist So which wrist watches are very accurate? None. For one simple reason. Non-EEG wearables cannot determine the moment you fall asleep. Strictly speaking, even your sleep charts are not accurate because you must adjust the non-EEG start sleep times to align with the EEG data. Otherwise, you would have blank parts at the front of all of your charts. Your viewers do not have the luxury of correcting their sleep start time to "fix" their somnographs. Wearing an EEG wearable makes wearing a non-EEG wearable (eg. watch) pointless. EDIT: Actually, the heart rate variability measurements provided by my Fitbit Sense 2 and Polar Unite are useful indicators of sleep quality/recovery. (But the somnographs are always very badly off compared to the Muse S and Dreem 2 graphs.)

[@gaboqv]

why would you need to know the exact start of sleep? this should only change results marginally around 5%. Also most people know how long it took them to feel sleep

[@brianquigley1940]

@gaboqv Fitbit, Samsung, and Polar watches all get my fall asleep time wrong... the "margin" is usually between 30 mins to 3.5 hours... how do you synch these without a baseline? Both the Muse and Dreem headbands show when I start a "sleep session" and when I actually fall asleep. Both synch accurately in how long it took me to fall asleep after lying down and closing my eyes. (And their somnographs.) I can't use the Dreem anymore as their site no longer works. But I still use the Muse (which has less information). I synch my "fall asleep time" with the Fitbit and Polar to check my "heart rate variability", which also often differ in magnitude. (Can't synch the Samsung.) In any case, the somnographs never match with the Muse (or previously the Dreem).