GPS distance on Charge 3 not accurate

[Marzipan61]

Any suggestions on what I can do to improve the GPS info interpretation of my Charge 3?  While on a run, with my Charge 3 communicating with my iPhone 11 Pro, I got my 1-mile cue, along with my pace, then 3 minutes later it communicated that I just hit my 8-mile mark.  Then, in an appropriate amount of time, I was at 9 miles.  When my run finished, the map was drawn and the milage given both seemed accurate, 2.5 miles.

2 runs ago, the Fitbit map drawn showed a lot if wrong info - it had me zig-zagging through the woods, wrong speed rates and wrong distances.

Thanks for your help.

Moderator edit: updated subject for clarity

[MarreFitbit]

Hi there @Marzipan61, welcome to the Community Forums. Thanks for bringing this to my attention and for the details provided about the GPS accuracy of your Charge 3.

Fitbit trackers and smartwatches calculate distance by multiplying your walking steps by your walking stride length and multiplying your running steps by your running stride length. We estimate your stride lengths using your height and sex. Track one or more runs using on-board or connected GPS, we evaluate that data to automatically update your running stride length. For best results, run at a comfortable pace for at least 10 minutes.

If you prefer to measure your walking and running stride lengths yourself and enter them manually, see How do I measure and adjust my stride length?

Note that when you're tracking an activity with GPS, Fitbit calculates your distance using GPS data rather than steps. If you begin moving before you get a GPS signal, the tracker will calculate distance using steps and stride length as described above until a GPS signal is found.

Keep in mind that your tracker uses your step count to calculate distance until it finds a GPS signal. In this scenario, your total distance calculated for the workout may be slightly less accurate than if GPS data were available for the entire duration. For more information, see How accurate is GPS?

After reviewing this factors, please go for another run and see if the distance improves. 

I'll be around, keep me posted. 😉

[FB111]

I've got the same issue with zag-zag lines being displayed indicating I'm walking into the bush.

I've used another tracking app called Relive simultaneously, hitting go on both and found a difference of Fitbit being around 20% higher - both use GPS.

Has there been any update to what was posted below?

Thanks,

Frank

[FB111]

PS. I've got a Charge 3 communicating with my iPhone X Pro