Amazfit GTR 2 Review: Sleep & Heart Rate Test (I wanted to like it...)

I tested the Amazfit GTR 2 against a scientific EEG device and tested the heart rate accuracy. Subscribe to my weekly Newsletter(!) on www.robterhorst.com
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Twitter: @QuantifiedRob
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The EEG tracker I used is called the Hypnodyne ZMax: hypnodynecorp.com/ from @HypnoDyne Corp
📹Fitbit Videos📹
Fitbit Charge 3/4 Sleep: • FitBit Charge 4 Ultima...
Fitbit Charge 4 Heart Rate: • Fitbit Charge 4 Review...
Fitbit Sense First look review and test: • Fitbit Sense Accuracy ...
Fitbit Sense Heart rate: • Fitbit Sense Heart Rat...
📹Apple watch videos📹
Sleep Cycle App: • Sleep Cycle App Review...
Steps: • Apple Watch 6 Step Cou...
Test: • Apple Watch 6 Accuracy...
📹First Garmin Venu Sq Video📹
• Garmin Venu Sq Heart R...
📹Oura Ring videos📹
Sleep Test: • Oura Ring Scientific S...
HRV Test: • Oura Ring Review: Hear...
Temperature Test: • Oura Ring Ultimate Tem...
📹Withings Scanwatch videos📹
Unboxing and first review: • Withings Scanwatch Rev...
Sleep test: • Withings Scanwatch Sle...
Heart rate test: • Withings Scanwatch Hea...
Q&A with Withings: • Scanwatch Q&A: Answers...
⏱️This comparison is part of a larger project where I spend over 11 hours a week tracking everything in my life. If you'd like to know more:
• This mad scientist sca... ⏱️
Timestamps:
00:00 General intro
01:29 GTR 2 Most Important Info
02:14 Results: Sleep Test Setup
03:19 Results: Sleep Test Comparison
07:16 Results: Sleep Test Overview
09:47 Results: Other Sleep Trackers
10:39 Results: Heart Rate Test
13:52 Results: Other Heart Rate Trackers
14:43 Conclusions
15:36 What Device Should You Buy?
16:09 Test Limitations
🎵Music🎵
(1) Not Without the Rest by Twin Musicom is licensed under a Creative Commons Attribution license (creativecommons.org/licenses/...)
Artist: www.twinmusicom.org/
(2) Wonders by JVNA
(3) Can’t Sleep (KZbin Audio Library)
(4) Classique (KZbin Audio Library)
(5) Blurry Vision (KZbin Audio Library)
Many thanks to Rob and Frederik (and his FUN:D SCIENCE FOUNDATION) for their help with the OpenBCI device.

[@aminek244]

What about the GTR 2 New Version accuracy please ? Someone tested it ? Thanks

[@jrsams5373]

Love your vids man. Thanks for such an in depth analysis. Awesome!!!!!

[@ggianne]

Don't know if you have already done but would be nice a table like in Google spreadsheet, updated after each test, with devices names and score for each sensor in the columns (heart, SPO2, ECG, Blood Pressure, exc..)

[@Aveiro17]

Thanks for your videos, awesome to see real data. Was thinking of picking this one up (the cheaper "e" version) , but found your channel yesterday, and this video is perfectly timed. Would be interesting to see the xiaomi mi watch and the oneplus watch. (and the ones you mentioned at the end) Subscribed!

[@drahmedelbaz]

Really like your reviews and appreciate the effort you put in them 👏.. love to see the analysis of a galaxy watch though

[@yeni353]

You make realy very efficent Videos for SmartWatchs, vielen Dank Herr Rob

[@jasonlin5460]

I bought this fitness tracker mostly because it had the best looks. Not the best HR tracking, but I'm hopeful it gets better with firmware updates.

[@RomainCavallini]

Awesome test as always, indeed it's a bummer that the tracking is so bad for such a nice looking device !

[@TheAmol297]

Love these videos. They are so detailed! Can you do a review of Samsung Active 2?

[@karlocirvencic3616]

I was waiting for this one.. too bad, but thank you for this review..interested in one plus watch now

[@Biocentric]

Can you please repeat the Amazfit GTR 2 heart rate test with the stress monitoring turned off? Many say that will make it accurate.

[@richie7091]

Hi Rob, great video as always. A shame to see such poor results from the GTR2. Do you have any plans to look at Coros products? Keep you the great work!

[@stanislavlee2145]

Thank you! Very interesting content!

[@alfo5322]

Hello, I sincerely loved the video, it takes a lot of effort and dedication, you have earned my subscription. I have the GTR2 and I was able to compare it to a medical grade EKG, and the measurement was very good in anaerobic ranges, but at VO2 max the measurement is about 6BPM below the real one. I assume it is a software problem that has already been fixed. Greetings from Argentina

[@trojjo]

I'm thinking of buying the gtr 2. So far, how has your experience with all of its tracking been?

[@georgesabikhalil186]

Great video as always!

[@wjofre1]

Was waiting for this one, thank you! I was hoping the accuracy wasn't THIS BAD. What a bummer, because the watch looks really attractive.

[@TheQuantifiedScientist]

Happy to help!

[@Mnkmnkmnk]

I was really considering the gts2e or the GTS 2 mini, because they look great with their amoled screens and long battery life. But not anymore. Really sucks because there is really no comparable activity tracker.

[@Kikwatz]

@@Mnkmnkmnk Huawei Watch GT 2 / Honor Magic Watch 2? They are even cheaper and seem to be more accurate.

[@catarinacamilo7286]

Will you make a review of the new GTR 3? I'm wondering if the heart rate sensor is better in this new version... Thanks for the videos, you are the best at reviewing smartwatches!

[@pd3022]

Hi Thanks for the great review. I have the GTR2e and GTS2e and I agree with your review. Yesterday however they released 1.3.18.02 and the heartrate detection seems a lot better(the changelog also states this fact). Would you mind testing the 2e with this firmware update? Thanks!

[@adrianvinueza6584]

Yes, that would be great. Maybe the doc just can publish the new results in a blog so He doesn't need to film another video

[@JustifyJustin]

@@pd3022 Thanks for the insight

[@trojjo]

I'm thinking of buying the gtr 2. So far, how has your experience with all of the tracking of gts 2e and gts 2e been?

[@pd3022]

@@trojjo I will be honest with you. I have since moved to a garmin venu2 watch, as the gtr2e/gts2e devices were not accurate at all. The venu 2 has been way more accurate. And I would not recommend spending money on the Amazfit devices.

[@Inzanti]

You ordered a great set of devices! Looking to the videos. I'm rather happy with my HB6's sleep tracking but have no idea if the stages are close to accurate 😂 Sleep score usually reflects well though.

[@c.m.7692]

Hey Rob! How much of the failure of this watch could you attribute to the software or the lack of data that Zepp Health has compared to competition? Or in other words, how much could Amazfit or Zepp get out of the BioTracker 2 given time and data? Or lastly if you'd prefer to talk in general terms: how much do you think activity tracking devices are limited by their hardware VS by their software... Besten Dank.

[@countach27]

Thank you for making this video! I've been contemplating buying a GTR 2e, but if it's this bad then I might as well stick with my Mi Band 4 for now

[@muriloprovenzi1571]

Amazing video, this does help a lot to instruct customers, thank you a lot for that! I am currently considering Amazfit Band 5, which you mentioned that are working on, do you have any expectation when you are putting it out? I am interested because Band 5 seems to use same sensors as GTR 2. Thank you again!

[@coffeenciggy]

Data (and facts) is king! A pity because it's a good looking watch. Thanks Rob!!!

[@kamrulhassan7185]

Great video as always. Do you have any plans to an in-depth review of Amazfit Bip U? That falls within the similar price range to other strong competitors Mi Band 6 and Honor Band 6.

[@Pr4gM4t1]

I wish this video was posted before I bought one (GTS 2 mini /mid Feb). The HR tracking is really bad, especially for activities with a lot movement of the arms, i tried a lot of combinations, sometimes work fine, but in many opportunities did not. Usually loses HR tracking, from 140-150 fall to 70-80. Sometimes never go over 80-90. And today the screen is dead, so no refund for me. Excellent reviews and videos.

[@elisabrischigliaro622]

Could you review Muse S and Amazon Halo please? I love how detailed and scientific are your analysis!

[@PouetPouet8]

Hey Rob ! Amazing channel and ideas ! You will probably become a reference for testing ! Do you plan to test the new GTR3 / GTS3 ? Also, i was wondering, is differents straps / bands have a effect on accuracy, could be very interesting to see measurement on the same watch with that variable ! (But you need 2x the same watch...)

[@dimalex8]

First time watching, and probably the best reviewer in KZbin. I like that you are not afraid to state your recommendation without any ifs and buts like other reviewers sponsored or not. Also supporting your conclusions with facts and real actual testing. Well done, you got a new sub

[@cityplanner3063]

Thank you for this information. That means most recent Amazfit watch’s all have bad tracking as they all use the same sensor, even the cheaper Bip U

[@diogopassagem]

this is a review thank you. If you can quantify you can manage!

[@Mnkmnkmnk]

Very nice to see such rigor for a youtube video.

[@Pachupp85]

one of the reasons why price of gtr2 is so good are videos like this. Thank you, i love my gtr2. ;)

[@ico.oliveira]

I just bought the new version of the GTR 2. I hope all of those issues were fixed. Haha wish I’d seen this video before buying. Thank you!

[@ernestchew88]

Please test the oneplus watch once it's out. Love how detailed your testing is. Thanks!

[@rishabhs14]

Agreed. Would be incredible if you could run your detailed review on the OnePlus watch. Super interested!

[@TheUnrealEgg]

I think an in depth review of the OnePlus Watch would gain a lot of views in general also

[@kleberbenedetiperes8113]

Congratulations on the excellent quality content! Could you test the Amazfit GTS 2 mini, please? Apparently it works very well, and much better than its older brothers (GTS 2 and 2e).

[@lucianoalmeida3249]

What tech combo (watch, ring, band, scale...) would you recommend to someone interested in keeping track of their sleep and overall fitness?

[@halooche]

Very interesting! I was very close to ordering this watch, I'm put off now after watching your video. It's a shame though, it is a very good looking watch with lots of features for the price. Do you think they can fix these inaccuracies with a software upgrade?

[@rizqyhbb]

Very very well presentation, I hope mi watch lite will be the next

[@amritkalash6750]

Awesome stuff man

[@guidoc3518]

Thanks, this is a true review.

[@johnyM128]

Hellou great review! It should be very interesting to see changes between old firmware and new one. Of there is better accurancy or not. If What a other watch do you recommend?

[@mroz8952]

Hello Rob, thanks for all information. Do you have any review plan for Amazfit GTS 2 and Amazfit GTS 2 mini ? Best wishes 👍

[@piiak6848]

I would also love to see a comparison especially with the mini as I have both units and it feels like the mini could be a bit more accurate 🤔

[@voodooparadox2513]

Thanks again! May I suggest the Google Nest Hub 2nd gen?! It would be interesting to see it’s sleep tracking!

[@jaboneros7540]

I hope you will also review the Coros Pace 2 soon!

[@danhattersley6213]

I have the gtr 2 and I love it, best smart watch I've owned, guess they have improved stuff since your review.

[@trojjo]

I'm thinking of buying the gtr 2. So far, how has your experience with all of its tracking been?

[@muhammadferdiansyahsanir1306]

I love mad scientist like this

[@ricardolazzaro]

Amazing video!

[@acarrizosa08]

I'm looking forward to your analysis of the Amazfit Neo. The GTR 2 uses a Huami-made sensor, but the Neo uses an older sensor (which does not include SP02, VO2max or HRV). I wonder whether the inaccuracies are caused by the new sensor in the GTR 2 or whether inaccuracies are also present in the Neo. If problems in one and not the other, then probably a sensor issue, but if problems in both then it could be either the sensor or the software causing problems.

[@Dirman_panembahan]

Hi , have u found any video that talk about amazfit neo accuracy? Could you please give the link, thanks in advance.

[@acarrizosa08]

@@Dirman_panembahan I have not found anything. I think it was never made

[@yonutz333]

Your tests are the best. Do you think amazfit gts 2 / gts mini would have the same problem reporting sleep wrongly?

[@joshsilva9807]

I love your channel! Would love to see more Apple Watch tests!

[@TheQuantifiedScientist]

Thanks Josh!!

[@nameberry220]

Please do the Amazfit Band 5! And also test sleep tracking with each available application, Zepp (official), Notify for Amazfit and Sleep as Android. The last two seem much more accurate!

[@bernardtan1]

Notify for Amazfit isn't more accurate than Zepp. It's way too much off. Can't even record or detect naps.

[@nameberry220]

@@bernardtan1 Yeah probably true, I'm using Zepp now, the band has issues syncing to more than two apps at once

[@riverthames4408]

This is amazing information that, as a normal user, I never would have found out if I hadn't watched this video. You mentioned that Apple Watch 6 is your recommendation for heart rate tracking, with the Fitbits taking over sleep tracking. Would you be able to recommend a smart watch that sits in the middle and does both well enough to be useful? Thanks in advance

[@lorandabos3120]

I'm curious, how likely is it that software/firmware updates will improve these measurements, is that something that typically happens with smart devices? I just ordered a gtr 2e mainly for the looks/other functions, but it would be nice to have tracking perfom at least decently. Great video as always!

[@tzeimet]

It's slightly better with the update. In this case I don't think it's the fault of the sensor, but rather the algorithm trying to filter out the true HR and any bad measurements. The watch essentially does not register HR which it thinks are anomalous e.g. if you're heart rate jumps up quickly, the watch is likely to register a lower value because the algorithm thinks it's a bad measurement, so sometimes it will register 80 instead of 160 bpm.

[@AnkitPaliwal]

Hey I really loved the way you reviewed. Yes GTR2 HR sensor was really bad.. specially during workout when you start sweating.. But device received couple of firmware updates. I request you if you can again check Amazfit GTR2/GTS2. Both have same hardware.

[@trojjo]

I'm thinking of buying the gtr 2. So far, how has your experience with all of its tracking been?

[@AnkitPaliwal]

@@trojjo i find it reasonably good for all activities except swimming. HR doesn't work for water activities

[@karoljedrzejewski7225]

Great content, are you planning to test other garmin devices especially vivo smart 3 soon?

[@invisibileism]

Thanks a lot for this much awaited review, too bad the watch was such a disappointment. I guess when you saw the sleep and heart rate results you decided that there was no point in testing the step counting :) I really liked this watch or the GTS2 but considered these results and what other users reported about the GPS and steps counting accuracy it seems there is absolutely no point. Thanks again!

[@Jnas-tc6zu]

Can you do a heart rate test for the amazfit bip u pro? That would be very nice

[@JuanSanchez-rb4qu]

Great video, tho its disappointing that amazfit cant even get its flagship right given how long they been on the market.

[@ismaelrivera1999]

Hey Rob, great review it really sucks that Amazfit is does has good fitness tracking. I wandered if this is true for all their tracking wearables.Could you review the new GTR 3 pro or maybe the Trex Pro. Thanks 🙏

[@verveblack]

companies should just send their devices to you for review before release so then can go back to drawing baord othwrwise ha

[@TheQuantifiedScientist]

Haha, great idea 😉

[@nomoshiti]

@@TheQuantifiedScientist , do you have any GTS 2 device? Like GTS 2 mini which I guess is the latest in the line.

[@singularity6305]

@@TheQuantifiedScientist thank you for your research!

[@danielbum912]

When HR trackers are this adamantly stuck at heart rates in the 75-100 BPM region while cycling I always suspect that they pick up your pedalling cadence over the heart rate. As in, pedalling causes your whole body to wobble slightly, up into the wrists, where the optical HR sensor picks up sine-like changes in brightness from periodical flexion to support your wobbling upper body... Or maybe I'm reading too much into it and it's just really bad & mostly guessing :)

[@billl1977]

We want a video about the amazfit GTS 2!!!

[@c.m.7692]

The GTS 2, GTS 2 mini, BIP u pro, the zepp e models and probably a lot more models all have the same sensor, BioTracker 2, so you ~~should expect the same results~~ [Actually it seams like there's a lot of variance between models and between same models but deferent updates. Biotracker2 is definitely capable of an accurate tracking see WesKnows jul. 9th video]. It could, and should, get better through updates though as zepp health gathers more data from users.

[@sjorswinkenius]

Could you review the mi band 6? It already came out so soon. I'm looking for a fitness tracker but I won't buy it until it has your seal of approval!

[@shrilankapati6446]

Please make one video on mi band 6 i really dying to see that video

[@gieddraz]

Really appreciate it! I nearly buy it...

[@grumelude]

I can confirm. I have a gtr 2 unit and the heart accuracy is really shameful. Regarding sleep tracking I couldn't make any comparison because I don't have any other unit to compare with but I already had a hard suspicion about how bad it performs.

[@samanthrajan2637]

U have the steel variant or aluminium one?

[@darwain7]

kzbin.info/www/bejne/bJTNandnqNJ0las

[@JustifyJustin]

Have you found any improvement with recent firmware updates to perhaps hint at solving or reducing many of the issues with heart rate and sleep tracking?

[@darwain7]

@@JustifyJustin everything is pretty accurste except for the deep sleep ill say but for the rest :) i have no regret

[@trojjo]

I'm thinking of buying the gtr 2. So far, how has your experience with all of its tracking been?

[@razlanhashim449]

TQ for the review sir. Do you know whether it can paired with the Polar H10 NHR sensor for a more accurate detection of the heart rate?

[@mikecar52]

Excellent video. I think I bought their first hrm watch and the heart rates were pure fiction not related to what I was doing.

[@ColakakiAa]

good job man

[@mrlawrencelam]

Under ZEPP > Profile > GTR 2e > Health Monitoring > Activity detection (When watch detects that you are doing exercises, it will automatically increase the detection frequency to guarantee the accuracy of heart rate data during workouts". I wonder if this is turned on when reviewing the watch?

[@mohammad...68]

Please reveiw this watch again after the updates

[@marcokoehler5020]

I bought this watch as a present for myself at Christmas since the cheap amazfit BIP S did quite well. I couldn't believe that it didn't work for me at all. I thought I must have a faulty unit since why should the more expensive gtr2 be a lot worse than the 60 Euro BIP S? Well I returned it and seeing this video it seems like it's just garbage. Such a shame, could have been a nice watch. The watch that I'm most interested now is the oneplus watch. I'm using the garmin vivomove luxe at the moment and it's 'ok', but something with more than 3 days Battery life that looks good and works well enough would be a reason to switch. Since amazfit is out of the game, apple and samsung don't even get 3 days - the oneplus watch could be the one.

[@castertroy2534]

Hi! Would really really appreciate it if you could also do the Amazfit GTS 2 Mini. Ive researched about it for 2 months and decided to buy it, it's currently on iys way now. Other resources I've seen have said it was pretty good. However this GTR 2 review is making me think twice. And I'm mainly going to use it for sleep tracking since my work is during the graveyard shift

[@jacobreubenaglipa5669]

Maybe you should get fitbit for assurance of the performance.

[@Wanderingfoodies]

Really disappointing results but really good content. Thank you for the video. Which watch do you suggest in same price range?

[@Lieyre]

I just have to thank you for creating that channel and that content. I do admit, at first I was kind of mad at you, since I really wanted to like this watch too and you ruined it for me! I wanted to buy OnePlus Watch but the reviews started rolling in about how inaccurate it was that I got interested at how accurate other smartwatches are and there is no other channel that really measures it. All the OnePlus reviews said to "Just get Amazfit GTR 2 instead" and your review made me realise it might be as bad or worse. But thank you for adding your own comparisons and suggestions in, will buy Huawei GT2Pro now!

[@sreepradakakani936]

Hey! How about the accuracy on GTS 2? As the design of GTS 2 & GTR 2 is different, is GTS 2 any better to GTR 2 in terms of accuracy? I am planning on buying the S one soon, so it would be a great help if I get a confirmation on this. Thanks in advance 😊.

[@BadaBing_]

I can't wait for Xiaomi Mi Watch test

[@Biocentric]

Can you please also test the Amazfit GTR 2e? Especially the heart rate, but with the stress monitoring turned off?

[@steffenvoigt5957]

Hallo and thanks for the video. Can see you had a bad experience with GTS 2. I don't know if you just have bin unlucky or the error has bin fixed since. It's very accurate now and i know because im a hjertepatienter. So im very pleased with it. 😊 Steffen Voigt Denmark

[@ananth889]

Is there are separate video for Amazfit gts mini 2 or this video is applicable for that as well?

[@gress12000]

I have the bip u pro. Is this the same for this model. Thank you for your review I was about to order this and decided not to.

[@weihao6061]

any plans to try out the latest amazfit GTR 4 series? especially after since 2 releases.

[@nyahbinghiman5984]

Could you make the video on best budget smartwatch that has most accurate readings?

[@mrsYnTTaX]

Can you make a review on the amazfit t-rex? thank you

[@emmarrem]

Hello Rob, Could you please do a review on the new Amazfit T-Rex Pro?

[@marcelvisser10]

Hi, can you also review the new Galaxy Watch 3? Previous Galaxy watches where really bad in detecting deep sleep. I am really curious of this is better with the new version..

[@czechnolike]

Yep, my mi fit 3 seems about as off I was dripping sweat for a hour long bike ride, and only measure an average 98 BPM.

[@McSuilenroc]

Are you going to be testing the GTR 3? Best regards

[@nikourasu2023]

Hi. Could you pls run a test on Huawei's GT 2 Pro and share your verdict? Thanks in advance

[@thedevsaddam]

Please test the GTS 2 which is similar to this one, but curious about this one

[@knusedabbetryne]

What is THE best sleep tracking watch/device per 2021?

[@drtuki]

I was literally just about to buy this exact model... now I don't know. Its performance (esp HR) is pretty bad :/ Great data and visuals! 11/10

[@danh9922]

Any updates on withing future video?

[@wizardnunes]

I didn't expect such scientific accuracy for a KZbin video, you sir just got a new subscriber!

[@Voyager602]

Best wearable tech channel ever

[@TheTTyks]

Hey! Will you test the Amazfit GTR 2E? Sincerely Johannes

[@tzeimet]

Interesting Analysis, I also noticed some issues with heart rate detection, the typical low heart rate issue. However, I must say the watch (GTR 2e) is accurate most of the time for me I would say around 80% of the time for cycling outside, it's sometimes a bit slow to respond to an increase in heartrate but otherwise pretty accurate for long distance cycling. I think that perhaps sweat is interfering with the optical sensor, for the money and the freedom from wearing a ECG band I definitely think it's a pretty good watch. The Apple watch is still the best for heart rate monitoring, but it's expensive and Apple specific.

[@JustifyJustin]

Have you found any improvement with recent firmware updates to perhaps hint at solving or reducing many of the issues with heart rate and sleep tracking?

[@tzeimet]

@@JustifyJustin It does seem to be better, but I still have issues with heart rate while doing sport the main issue is that the watch sometimes registers an abnormally low heart rate for example 100 when doing heavy exercise when my normal heart rate should be 180+. This issue usually goes on for 30 minutes to 1 hour then the watch suddenly shows the correct heart rate for the rest of the acitivity. The sleep tracking seems inaccurate, as it only shows a few hours of deep sleep a nihht, but I don't have another watch to compare it to. I'm pretty sure heart rate while sleeping is accurate though and the total hours slept is also accurate.

[@JustifyJustin]

@@tzeimet Thanks Tom. In that case it seems Amazfit still has some development needed. Appreciate the feedback - I'll look at getting a Mi Watch. Thanks.

[@tzeimet]

@@JustifyJustin No problem. I think if sports tracking is a big priority and you're willing to spend more, then maybe a polar watch along with the OH1+ armhand optical sensor might be interesting. I've heard and read some good things about it, probably the best alternative to an ECG chestband. kzbin.info/www/bejne/p4Cpia2dqcdmm6c

[@trojjo]

I'm thinking of buying the gtr 2. So far, how has your experience with all of the tracking of gtr 2e been?

[@dr.vamshikrishna1002]

i can see newer version of amaze fit GTR 2 in online sites, is this analysis applies to older version or for newer version also ? please reply if possible

[@jeshanrajganeshwaran4990]

Bro, do you recommend this watch or the huawei gt2?

[@kiranbabukk6673]

Thank you,