Charge 6 - HRV is recorded as 0 (zero)

[9Ab33]

What is the reason the device sometimes doesn't measure HRV, and how can I make sure it does so every night?

The device works perfectly for the exception of it not measuring HRV sometimes. 

I'm wondering if this is a bug or if my device is broken.

Over the last month, it's only recorded my HRV 35% of the time.

Moderator edit: updated subject for clarity

[DavidFitbit]

Hi @9Ab33, thanks for stopping by, I hope you're doing well.

Let me help you with your HRV measurements. 

Fitbit uses the common formula called Root mean square of successive differences (RMSSD) to determine HRV from your recent heart-rate data. In the graph, your latest HRV measurement is from the longest sleep period over the past 24 hours. Only sleep periods greater than 3 hours are considered.

If your HRV hasn't been measured, see how you can improve the accuracy of your heart rate reading by following the suggestions in our help article How do I track heart rate with my Fitbit device? > How to I improve the accuracy of a heart rate reading.

[9Ab33]

I follow the advice given in the link, and the problem still persists. What now?

[DavidFitbit]

Hi @9Ab33, thank you for your response and for trying the suggestions proposed.

It may be possible that the HRV from previous night won't be shown retroactively. However, did you get any HRV either? Does your device properly read your heart rate during the day?

In any case i recommend that you force quit the Fitbit app on your mobile and ensure you are running the latest version. You may refer to the following link to force quit the app Close an app on your iPhone or iPod touch. To update de app go to How do I use the Fitbit app? > How do I update the Fitbit app?

[Bousso]

I recently started getting the same problem with my Fitbit data. It tracks everything, but HRV shows as zero some nights. This started happening since a few months ago. Seems like it came after all the Google transfer business and updates

[skylargh59]

I had the same issue starting last week. My HRV is usually one hundredy twenty five to one hundred fifty, but every other night its 0, which doesn’t make any sense 

[JeanD88]

I am also experiencing similar issues. I’ve restarted both my watch and my phone. I uninstalled the app and reinstalled…there seems to be a serious issue.

 Example: One night I had an HRV of 149, the next day it was in the teens.

 It shows me as being awake when my heart rate was at its lowest (and I was sound asleep).

 My “average” HRV is mathematically impossible.

 And more disturbing I now have a zero HRV so I suppose I’m dead now lol!

 Please help!

[agnosie]

My HRV was recorded as "0" last night. All other measurements work and I am premium customer. Sleep duration according to fitbit was 7 hours with an index of 87. HR was in 90% of the time below the resting heart rate.
What kind of a bug is this now, to state that HRV is "0"?
Please solve this nonsense as it has effects on other metrics.

[Carol625]

Same issue here - I had a zero three nights ago, a 114 (!) two nights ago and a 0 again last night. I completed the most recent update yesterday and the problem persists🙁

[ohiohhh]

How is everyone's HRV over 100?? Mine is usually 0 to 40. I don't think I've ever seen it once over 100 and I've had a Fitbit for like 8+ years. 🤔

[KATWILL63]

I know I know it’s not supposed to be a medical device but it helps me kinda know where I’m at. I am a premium member. There seems to be an awful lot of bugs and problems for $80 a year, but it upsets me when it shows my HRV is zero no breathing rate there’s always some kind of problem because I just seriously cleaned it last night restarted it on purpose it was fully charged. I wiped it off before I put it on as always 2 to 3 fingers up my wrist as always I’ve had a Fitbit for three or four years About time to break out the Apple Watch 10 I was gonna use this Fitbit until the end of this membership because I kinda like it I just wanted a small tracker and it has a easy format but the sleep score is what I really go for and it’s always messed up. It seems like it goes good for a while and then nothing while they’re experimenting on our $80 a year just rambling because it keeps happening frustrating frustrating nobody wants to Google pixel they want the small tracker if they were smart they would keep it make it better and keep charging the $80 a year only make it work. Also make it see it was more senior friendly and now it’s all peloton everything which I get everybody needs to be covered though sorry this was so long. 

[KATWILL63]

There was an update last night. Mine was 02 and some other metrics were missing again. That’s why I pay $80 a year. You expect some problems but not frequently I like this little tracker. I don’t want a big watch. I like the easy interface, but when it keeps having problems, it makes me think Anyway good luck to everybody. The heck of it is I just cleaned it cuddled it, baby. It restarted it made sure it was wiped off perfectly and put on perfectly last night so I would get a good reading and this morning nothing

[agnosie]

My HRV was recorded in the last two weeks three times with "0", all other data is there and in line with what I would expect.
This HRV becomes really annoying and I would like to have an explanation for this.
What is the algorithm that can create such HRV values. Is it published anywhere?
I would appreciate if a moderator can comment on this issue.
Thank you!

[agnosie]

and again HRV recorded as "0" 🤔

[agnosie]

And once again, two more days with an HRV of 0. Does anyone know where the HRV (Heart Rate Variability) is calculated? Is this calculation performed by the Charge 6 device itself, the app, or on the server/cloud?

Answers from a moderator are welcome.

[CamJo]

Same here! I always have it on (have tracked sleep every night for two years) and this morning it could not sync. After restart it only showed total hours of (+7hr-ish) sleep (no graph) and also HRV 0. I'm normally 23 to 27. What is happening and is there anything I can do to fix it?

[PutPutAK]

I have read all of these.  I am a paid member and am tired of the HRV dropping out.  Been happening for a couple of months.  CAN I get my money back?  All the other metrics record on my phone without the fitbit.

[DavidFitbit]

Hi everyone,

Thanks for letting us know about this issue in regards the heart rate variability as zero. We’re aware of it and are working to identify a resolution as quickly as possible.

I'm sorry for any trouble. I appreciate your patience and we look forward to getting you back on track. In the meantime, make sure to have the latest version of the fitbit app installed in your mobile. For reference, see How do I use the Fitbit app?

[My1stchoice]

Has there been an update on this issue? It keeps happening and I noticed it only happened after the google migration I have never had this issue prior to that. 
I spoke with one of your colleagues on the phone and was told I could get 35% off my next device! Exciting times… sadly I feel even if I did so the problem would persist as it is a software issue/bug from your side. 
Please advice on when this issue will be resolved.

[PutPutAK]

I bought a new one…problem persists.

Sent from my iPhone