Charge 3 calories not accurate

[Dave_M_G]

Since 2015, I have owned a Fitbit Charge, Charge 2, and I now currently own a Charge 3.

With the Charge 1 and Charge 2, I found the calorie burn rates were in line with my expectations. I keep meticulous records of my calorie intake, and record my results with the help of a body fat % measurement machine at my gym. With the help of my Charge 1 and Charge 2, I was able to meet my goals pretty much exactly on target.

Since getting my Charge 3 about a month ago, almost right away I could tell something was off. My exercises were showing high calorie burn results. Then I found that I was gaining weight.

I still had my Charge 2, so I tried wearing both for a while, and discovered that the Charge 3 is reporting around 10% more calories burned than the Charge 2, as can be seen in the pictures below.

While it would be nice to think that the Charge 3 is now more accurate, meaning that I've been burning more calories than I've thought for the last few years, that just doesn't seem to be the case. My record keeping since before owning any any Fitbit, and through owning the Charge and Charge 2, has been consistent, and the Charge and Charge 2 provided predictable and consistent results. The outlier is the Charge 3. For the Charge 3 to be accurate, it would mean everything else I've ever done is wrong, which is not impossible, but a strong case would have to be made for where I'm going awry.

Is there any way the Charge 3 can be calibrated to lower the burn rate? Is there a flaw in the way it is calculating calories? What are the options for dealing with this?

Moderator edit: updated subject for clarity

[StillExercising]

I just found this thread and seem to be having the same problem--my Charge 3 is overestimating my caloric output. I have kept detailed records of my caloric intake and output for 35 years (I'm in the health sciences). My old Alta recently died and I purchased the Charge 3. I have synced my Fitbit stats with Lose It since 2012 and previously used pedometers and before that just plain estimates. For years, the records were consistent with each other and with Harris-Benedict & Mifflin-St. Jeor. When I switched to the Charge 3, step count stayed consistent but total caloric output and exercise adjustment both jumped dramatically. Recent sample: TOT WEEKLY ALTA STEPS = 77000 vs CHARGE3 = 75000. TOT WEEKLY CALORIE OUTPUT ALTA = 19000 vs CHARGE3 = 22000. TOT WEEKLY EXERCISE ADJUSTMENT ALTA = 2400 CALORIES vs CHARGE3 = 4500 CALORIES. I ain't exercisin' no 4500 cals per week. Any help appreciated.

[SoberDadLiving]

I searched everywhere and just found that the Charge 3 kinda sucks for
calorie counting. I wish I had stuck with my Samsung. The only thing I've
found to be reasonably accurate is to subtract 20% from my daily or weekly
averages. As far as during exercise periods though good luck... I've had
my Charge 3 tell me I burned nearly 2000 calories lifting heavy in the gym
for 2 hours, at in reality it was maybe 400 calories.

"Believe nothing merely because you have been told it. Do not believe what
your teacher tells you merely out of respect for the teacher. But
whatsoever, after due examination and analysis, you find to be kind,
conducive to the good, the benefit, the welfare of all beings -- that
doctrine believe and cling to, and take it as your guide." -Siddartha
Gautama

[StillExercising]

Thanks for the workaround, I’ll try it. But after all these years and
technological advances, what a disappointment!

[Devinps]

Unfortunately this workaround won’t work for me. I never use the exercise modes but my Charge 3 still reports 3500 calories burned a day.

I’m sedentary and my BMR is 1900. So my very light activity should bring total cals up to 2200 or so max.

This ridiculous device is adding an additional 1300 calories to my daily burn record. Absurd and frustrating! 

[SunsetRunner]

Hello, I just bought a fitbit charge 4 and I see that it really overestimates my calories burnt.

Is there a way to fix this? 

It's not just by 4% but 40% I think. 

[SoberDadLiving]

Nope, the more active you are the more inaccurate it is. Make sure it's
tight on your wrist with constant skin contact for any degree of accuracy.
Also get an RMR test (resting metabolic rate) so you can more accurately
calculate how inaccurate the device is.




"Believe nothing merely because you have been told it. Do not believe what
your teacher tells you merely out of respect for the teacher. But
whatsoever, after due examination and analysis, you find to be kind,
conducive to the good, the benefit, the welfare of all beings -- that
doctrine believe and cling to, and take it as your guide." -Siddartha
Gautama

[StillExercising]

Yes, sadly, the energy expenditure estimate is just not accurate. After posting back in February, I contacted customer support and asked that they look at this thread and perhaps refer it to their research/development dept., which I doubt they did. The support people were very nice and had me try all the usual things--reboot, make sure app is up to date, tighten wrist strap, etc. They politely told me that the heart rate monitor detects when I am in my fat burning zone and I politely told them that I know this but that the calorie expenditure is still too high. So I turned off the heart rate monitor and voilà, the calorie estimate is accurate. I then found a couple of studies that concluded that while fitness trackers (Fitbit & others) are good at steps, heart rate, etc. they are simply not accurate at calculating calories burned. Since I am using it for calories, I have turned off the heart rate monitor and now miss all those data; I turn it on only when interested in heart rate. Sad and frustrating, but I guess that's the limit of the current technology. 

[SunsetRunner]

Thank you for your answer. Ok I will turn off my heartrate measuring and see if it helps. 

[StillExercising]

Good luck and let us know!

[timmermanshan]

How do you turn the heartrate off?

[StillExercising]

Hi!
>From the home screen swipe right to left 3 times. You’ll the see
“Settings”. Tap on it and scroll down, find “heart rate” and tap on it.
Good luck!

[timmermanshan]

Thanks 🙂

[STLcomet]

@StillExercising I'm curious, was the heart rate or resting heart rate itself accurate compared to your historical measurements? I wonder if the charge 3 is measuring too low on the RHR, meaning it takes more energy to raise your heart rate to get to each exercise zone which would give an exponentially higher calorie burn. If that's the case, then there is an option where you/we can manually change the heart rate zone levels for each category i.e. fat burn, cardio, peak. I'd very much appreciate your feedback. Thanks!

[timmermanshan]

Yes i saw this in the app..and thought of changing it..but dont know.. what to set🤷‍:female_sign:

[StillExercising]

Hmm..that's interesting. I seem to recall that while my active heart rate
was accurate, my RHR might have been a bit low. I'll switch back on the
heart rate and do comparisons and let you know. Thx for the suggestion!

So I checked my heart rates and they are accurate. I then altered the heart rate zones by manually setting my max HR at 140 and then 170 so I could compare daily calories expended with no HR vs the default (max HR 150) vs max HR 140 vs max HR 170. The daily cals were still much lower (and more accurate) with the heart rate monitor off. There was not much difference among the 3 different max heart rates and they still gave me too many daily calories. Oh well, it was worth a try!

Moderator edit: merged reply

[DrewPrezz]

Out of Curiosity? All of your data has been consistent with all of your athletes, any outliers? You offer a lot of insight considering you use it and you have a multitude if athletes using it as well. While comparing it to Legitimate calculations/tests. Could you offer more insight?

[StillExercising]

I'm confused, or perhaps you are. I don't work with any athletes. I'm just
one guy trying to figure out how to get the daily calories burned measure
accurate when the heart rate monitor is turned on. I found this thread a
number of months ago while searching Fitbit Community and it seems that
many people who have posted on here have the same or similar issues. So I'm
unaware of any outliers, unless those of us with these issues are the
outliers. Since I was unable to get through to the Fitbit research
department, I have no idea what their data shows. And only speaking from my
own data, every time I use the heart rate monitor, my Fitbit shows
unrealistically high calorie output inconsistent with my years of
fine-tuned record keeping. Hope this helps!

[JeanGr]

My charge 3 is recording that I burn 500 to 900 calories per day... Even when I don't use it. Is this an assumption that have been placed as a normal calorie count even when a person is not doing any workout activity ? 

[StillExercising]

Yes, the Fitbit uses BMR calculations to estimate calorie burn throughout
the day. Follow this link & click on the Calories Burned section:
https://help.fitbit.com/articles/en_US/Help_article/1141.htm#calories

Hope this helps.

[CarolSauer]

Hey guys Im having the same issues

I exercised using my Charge 3 and a Apple Watch i borrowed and the heart rate was the  same but the calories on Charge 3 were much lower. The same happened when I tested with a Polar watch

I do cross training, very intense, but Charge 3 shows me 230 calories burnt max

No way this is accurate. 
What should i do?

also, what is The correct exercise mode for crosstraining?

tks