Charge 6 is showing incorrect heart rate during workout

[hammadraza]

My charge 6 arrived last week. The first day I wore it to the gym it was showing the correct heart rate compared to the Galaxy watch (P.S. I wear Galaxy watch 5 pro on the other hand). But from the next day, it stops tracking heart rate. The heart rate is constantly less than 90 on Charge 6 and Galaxy watch or even my old Fitbit Charge 4 is tracking the correct heart rate.

One interesting thing is that compared to Galaxy Watch or Charge 4 the calories burned are almost the same but on Charge 6 there are no active zone minutes during a 2-hour workout.

I tried restarting the Charge 6, but it doesn't help.

[susan.t55]

Hi ,I’ve now been using my charge 6 for just over 3 months so as an update I can confirm what you say ,it seems that until you get into the cardio zone for a prolonged period of time it just seems to wave around 90 or so with no zone minutes.Once into cardio though it seems to do a bit better and I think sometimes even overestimates the higher end of the heart rate.Am not thrilled with the charge 6 but now I seem to understand it a bit better and after having worked round some other early set up issues I’ve adapted to the results, including having lower active zone minutes otherwise it’s exhausting!

[MelissaDM]

Same problem. It's accurate most of the time, but during intense workouts, it flatlines...which is frustrating because I don't benefit from the motivation of all those zone minutes. For an expensive watch, it is disappointing. I just return my versa because it was burning my wrist. Now this. It'll be my last fitbit.

[JenniferVWink]

My Charge 5 screen went blank & wouldn’t return. So- I ordered the Charge 6 with expedited overnight shipping. I have been walking for hours - and show 0 Zone Minutes & a very low heart rate. I was getting between 230 to 350 zone minutes each day on my Fitbit 5. Should I return the 6!& get a new 5?

I wish I knew this was an issue before I purchased. 

[marione84]

Same behavior here...
I had a charge 4 which worked fine for years, now i've replaced it with the newer 6, and I noticed that during hiit or wheight lifting the heartrate is lower by at least 30 or 40 bpm more or less.
I'm very unsatisfied because the hartrate monitor reading error is too big. I can accept an error of 4-5 bpm, not 40!

[JenniferVWink]

Yeah. I’m still having the same issue. I switched to a tighter band/ thinking that might be the issue. 

It seems that once I’ve been walking for over 3 hours, it starts showing a higher BPM (yet still not nearly as high as my Fitbit 5). 

There have actually been times when I’m winded & it shows my BPM as lower than my resting heartbeat. I would average 300 to 350 Zone Minutes on my prior FitBits. On the Charge 6, I’m lucky to get 200. 

I just think there is genuinely something wrong with it. I wish they’d just admit it. 

[LDinmotion]

I had the same problem with my new Charge 6—wildly inaccurate heart rate readings during vigorous exercise (typically 30 to 40 beats behind the rate shown by my Charge 2, which I had always found to be accurate and which I wore alongside the new device during exercise).

I have solved this problem to my satisfaction by using a number of suggestions made on this forum and on YouTube videos; by trial and error, I found a combination of actions that work for me.

First, I purchased a stretchy watchband to use during exercise since this type of band causes the device to fit better than it does when I wear the band that came with the Charge 6. (I actually bought a set of 5 bands, all different colors, from Amazon. The brand is Folavii, and the cost was only $12.79.)

Next, I rotate the Charge 6 just before exercising so that the sensor is on the underside of my arm, about two fingers’ width above the wrist.

The last extra step is to place a bunion pad under the watch. I purchased a set of 5 Dr. Scholl’s Bunion Cushions from Walmart for $4.97, and now, a month or so into this experiment, I’m still using the first one from the set. I trimmed away the outer edge of the pad so that it is closer to the size of the watch, and I left the paper coating in place so that the adhesive part of the pad is covered up. The paper part is worn next to my skin.

The results: when I compared the average heart rate reported by my two Fitbits after half an hour of aerobic exercise, the difference ranged from zero (which happened twice) to seven (which happened once). Typically, the difference is three or four, which is acceptable to me. Interestingly, the Charge 6 sometimes reports the higher number, and, at other times, it is the Charge 2 that indicates a higher heart rate.

I hope these suggestions will be helpful to other Fitbit Charge 6 users who are dealing with the frustrating problem of inaccurate heart rate readings.

[rckcold]

I am facing a similar issue. When I walk on the treadmill it shows my heart rate just above 100. Then when I use the rower it shows my heart rate in the 80s even though I am completely out of breath. Walking I am not even close to putting the effort that goes into rowing but it shows a higher heart rate. Makes no sense. Never had this problem with my Charge 5.

[dhimes]

Can you speak more to the bunion pads?  I also reverse my watch (and shave that part my wrist- I suspected that hair was the culprit and I'm a hairy guy), but I didn't know about the bunion pad.  Does it sit behind the watch (and somehow not interfere with the reading), or behind the buckle or snap of whatever on the bands you are using, on the opposite side of your wrist from the watch?