inaccurate heart rate readings

[kindzmarauli]

My Charge 5 (purchased in July of this year) occasionally shows heart rate way too high - 80 or 90 where it actually is under 60. Here is one example:

Charge 5 heart rate

I was home all day, did not do anything to get my heart rate up. Randomly checked the device - the heart rate is 90+. I would normally feel it when my heart rate is this high - and this certainly didn't feel like 90. Checked my heart rate with a timer it was around 55 - all the while Charge 5 was still showing 90+ and then slowing down to 80 and 70.

This happens sporadically a few times a month or perhaps more often - can't be sure - but know for sure these readings are inaccurate.

Questions:

• Is this a known / common issue with the device?
• If the device for any reason (position on the wrist, dirt on the sensor, any other issues) can't produce an accurate reading - shouldn't it say so, as opposed to reporting a clearly inaccurate one?

Thanks!

[KChumley]

I have this exact same issue. It’s bothersome since I only bought my Fitbit in July and this is one of 3 issues I’m having with it. Resetting it doesn’t fix any of them. 

[Ehauck]

I am also struggling with this! It tells me my HR is at one hundred seventy five(175) to one hundred eighty five(185) while exercising sometimes but other times it is at 120. When it says it is this high I manually check my heart rate and it is WAY off. This in turn screws up my calorie counting and tracking as it tells me I’ve burned more calories than I really have. I am so frustrated! 
I read an article to wear my tracker tighter while working out…if I wear it any tighter I’ll cut off circulation. This is very disappointing as I’ve been a loyal customer of Fitbit for years but I am really thinking about finding something different as I continue to have issues with my different trackers I’ve purchased!

[kindzmarauli]

Thanks for reporting your observations, @Ehauck and @KChumley! (175?! That's really high!)

After experimenting with my Charge 5 more and a fruitless exchange with FitBit Support - I can sort of induce it to report inaccurate heart rate: drumming or rapidly tapping something for a minute would usually (but not always) force the device's reported heart rate to go up. How tight the band is around my wrist doesn't seem to matter - yet it seems that the wildly inaccurate heart rate readings happen in a couple of scenarios:

• certain types of motion or activity (like drumming)
• after the device "wakes up", i.e. after inactivity. If I put it on and walk around for a minute, I often see the heart rate readings at 70 to 90 (or higher) - and if I measure my heart rate with a timer or some other way at the same time - it's around 55.

So it's probably a combination of hardware and software problems that likely affect every Charge 5 (and maybe other devices) that I am hoping FitBit will fix at some point.

[SunsetRunner]

You would think that with all the multiple complaints. I have at least 3 with tech support for mine. 2 months old and once again stopped recording heart rate. If you purchased a brand new vehicle that only worked 1/2 the time it would be called a LEMON.

Fitbit, what do you call it when the HR functions stop?? The sleep function NEVER records the actual time I go to sleep, but can record me taking a NAP to the second.

I am contacting tech support one last time, you know if you do NOT follow the 14 step program to process a return for defective merchandise, you will only get another used product.

[Allistar]

I've noticed that my FitBit is relatively accurate when I'm resting or doing light exercise like walking, but it significantly under reports my heart rate when I'm mountain biking. I wear a Wahoo Tickr strap which I consider to be accurate. When my heart rate hits 180bpm the FitBit only reads 130ish. For a 4 hour ride if my average is 150 as reported by the strap, the FitBit has an average of only 120. That's a big difference.

I have it tight enough on my wrist. Could sweat cause inaccurate readings? Or is the the vibrating from the ride?

[Superficies]

I've had a similar issue.  When I manually set the Charge 5 to record exercise, it either a) shows no heart rate at all (just "--", or b) shows my heartrate about 50bpm higher than what it actually is.  If I turn it off, it shows my heart rate as normal.  This ONLY happens when I manually set the watch to exercise.

It will right itself, but it takes a few minutes, regardless of if I clean it, reset it, etc.