Wrong distance measured

[21maximillian]

Hi there, 

Been using my Charge 2 for a few weeks now. It's the first fitness tracker I've owned and I've been loving it but I had an issue with the distance calculated on my last run. Hope you all could help me with this. 

So I ran my usual route last night, which is about 6.2km. I run with my iPhone 6s strapped on so that I can use the connected GPS function. In all previous times I ran this route, the distance measured was between 6.15km - 6.25km. However, last night it measured the distance to be 4.88km. This was rather annoying for several reasons. One, when I was running, the pace displayed on my Charge 2 was way slower than my usual pace. This made me doubt my fitness and I ran faster than I had intended to. I ran my best time for the route, which is nice, but... Two, my Fitbit shows that I only ran 4.88km! Three, I had just recently bumped up my cardio fitness score but after my run yesterday, it went back down by a point, which is a little demotivating. And four, I'm afraid that my stride length calculations have been affected because the steps counted on the run were similar to the numbers counted in my previous runs. 

Couple of questions:

1a) Any possible reasons for why this might have happened? 

1b) How do I prevent these from happening again?

2) Is there any way for me to correct the distance on my last run?

Thanks all! I'm really enjoying my Fitbit so far but if this happens repeatedly, it'll affect my experience of it. 

[shipo · Accepted solution]

---

@21maximillian wrote:

Hi there, 

Been using my Charge 2 for a few weeks now. It's the first fitness tracker I've owned and I've been loving it but I had an issue with the distance calculated on my last run. Hope you all could help me with this. 

So I ran my usual route last night, which is about 6.2km. I run with my iPhone 6s strapped on so that I can use the connected GPS function. In all previous times I ran this route, the distance measured was between 6.15km - 6.25km. However, last night it measured the distance to be 4.88km. This was rather annoying for several reasons. One, when I was running, the pace displayed on my Charge 2 was way slower than my usual pace. This made me doubt my fitness and I ran faster than I had intended to. I ran my best time for the route, which is nice, but... Two, my Fitbit shows that I only ran 4.88km! Three, I had just recently bumped up my cardio fitness score but after my run yesterday, it went back down by a point, which is a little demotivating. And four, I'm afraid that my stride length calculations have been affected because the steps counted on the run were similar to the numbers counted in my previous runs. 

Couple of questions:

1a) Any possible reasons for why this might have happened? 

1b) How do I prevent these from happening again?

2) Is there any way for me to correct the distance on my last run?

Thanks all! I'm really enjoying my Fitbit so far but if this happens repeatedly, it'll affect my experience of it. 

---

Last question first; I do not believe there is a way to correct a run.

As for accuracy, kind of a fact of life when it comes to GPS and other location fixing logic (typically from mobile phone towers).  There are occasions where most (if not all) GPS devices lose their fix (due to tree foliage, buildings, clouds, mountains, position of satelites, and general effing magic) and need to resync with the satelites; when this happens the tracker will need to rely on your stride length setting in your profile until a new location fix is established.  I would say one in fifty of my runs is impacted in this manner, and at this point I simply ignore it and move on to the next day/run.

[21maximillian]

Thanks shipo! Let's hope that this happens to me only 1 in 50 times too. 

[PBa]

This happens to me 100% of the time and it sucks. I'll run on a treadmill and do a 5k and it'll tell me 3-4. I'll do interval training and run a 1 Km race track loop, it'll tell me 0.7-0.8 k. 

Its just so grossly inmacurate ive given up on using it to measure distance and pace.

[TaniaMichelle1]

I am on my second fitbit charge 2 tracker and my routes still do not track properly, I have been

running for years and know the distance of all the routes I do.  I run with the GPS on and every run

I have done is approximately 0.7 of a mile out for example I run 4 miles and my pace varies between

8.13 and 8.20 but my tracker states I am running 3.25/3.29 with a pace of 10.03 or 10.10.  I also do

various workouts i.e. Zumba, Piloxing, Body Combat etc and they provide similar calories burned which I find highly unlikely, I think this is measured generally on the length of the exercise classes.  I would not recommend anybody buy a fitbit if they want accurate readings. Why should I have to measure my pace to try and get an accurate distance?  My first tracker was less than 7 days old when it was apparent and also confirmed by fitbit that the steps were not tracking correctly, they replaced my brand new FAULTY tracker with a refurbished tracker and stated that I should have been aware of this as it is in the terms and conditions before you actually set up the tracker.

[TonyMc]

I do the same ride several times a week (commute to and from work) with a Charge 2 and the GPS from my mobile phone.

The distances recorded vary a lot, from 6 miles to 9.7 (actual distance is 9.7 miles).

I raised the issue via Twitter and got:

* you need to update the firmware (but was on the latest firmware)

* your GPS signal must have dropped out (but the mapping was the pretty much the same each time)

I have used the GPS on several longer rides and the mapping is usually pretty accurate, but the measured distances are useless.

Apparently this has been passed to the engineering team...

[TonyMc]

This is not the case that I have stated, as the GPS has plotted accurately on the map. It is the Fitbit App that cannot accurately measure the distance covered. I have had very similar plots on multipe days, but with widely varying distances according to the Fitbit App.

At the moment I have given up with the Fitbit App for tracking distance, speed and effort. 

I am currently using Polar GPS and a chest strap for HR, until Fitbit actually resolve the issue.

[Rich_Laue]

@TonyMc I see no mention if your tracking a walk or run, I have not gotten confirmation from Fitbit yet, but several users say they have confirmed that while walking Fitbit still uses the stride to detect distance. My tests also confirm this. 

[MakarandGodbole]

In my case this is not 1 in 50 runs. this is an everyday event. and that is disturbing.

[Rich_Laue]

@MakarandGodbole since this is your first post, could we get a little more information? 

You say it is everyday do you;:

Carry the phone with you? 

See a map of your run? 

[piedwagtail91]

same for me. it told me 1.6 miles for a 10 mile walk today. My charge 2 is looking more like an expensive piece of rubbish every day.It was accurate till the updates, now i 'm thinking of using a  stopwatch and literally putting this under the hammer. 110 minutes to walk a mile. i think not.

[shipo]

---

@piedwagtail91wrote:

same for me. it told me 1.6 miles for a 10 mile walk today. My charge 2 is looking more like an expensive piece of rubbish every day.It was accurate till the updates, now i 'm thinking of using a  stopwatch and literally putting this under the hammer. 110 minutes to walk a mile. i think not.

---

How did you use your Charge to track the walk?  GPS mode or just the old fashioned Steps times Stride Length?  If you used the latter, did your Charge track the appropriate number of steps (roughly 20,000 for the walk)?  If it tracked the steps correctly, what is your walking stride length set to in your profile?

[MakarandGodbole]

I do carry my phone with me. please see the detailed email with all
screenshots, sent to you.
This is very disappointing. you say your engineers are aware of the
problem, and yet are not talking about replacement within warranty.
I had to go out and buy samsung fit 2 pro, and i have found it works better
than you.
Regards
Makarand Godbole
I am informing croma about this incident and your responses. I will be
demanding a refund or replacement from them. if not it is to consumer court.

[andyv1]

I also get the distance wrong occasionally, but it’s giving it more rather than less so my pace is unfeasibly fast.

Oddly it seems often to happen on Sunday, so I wonder if GPS is overworked then, or on partial standby.

Spoiler

[MakarandGodbole]

You are amongst the fortunate ones. It seems my fitbit is never satisfied
with my workouts!

[Rich_Laue]

@MakarandGodbole your postsoundspolike it is addressing simebody but there is no mention of who your addressing. 

[andyv1]

There is also another factor to consider. I track exercise on my phone, but tend to view it on my ipad. It’s really important to ensure before a run that the phone is coupled and the ipad is not. In my case if both are on and in range with the fitbit  it will preferentially pair with the ipad. When I run away from base the ipad loses contact and the phone tries to connect. It generally gets pretty confusing if I don’t check which device is on or off.

[Rich_Laue]

@andyv1 what your describing is the way Bluetooth works. There is a feature request to add the ability to choose on the tracker what device to sync through, this could bean answer .

[Manousaki]

Hello everyone,

The same issue affects me too. I recently ran a 10K race where Fitbit calculated 9 kilometers. During my workouts I track my distances with other apps and Fitbit always calculates less. Is there a way to actually resolve this?

Thank you.

[tdwalsh]

Hi, I hate to beat a dead horse, but this one is still kicking. I had a surge for 5 years and it was awesome to the very end. I got a charge 5 for christmas and it's inconsistent. the 5k course (3.1 miles) measures 3.49 miles. Surge was always very close. This is way off. Another park we usually run is right on the money with what the surge clocked. Everything else is wrong. I say "wrong" because some courses I've not only clocked with my surge, I also clocked with map my ride and compared to others who use a garmin. Sunday's 4 mile course came back at almost 4.6 miles. Last night's 4.1 run came back as 3.65. It's a device issue. I feel I got a cool new display but lack of accuracy and functionality.