Gps tracking on charge 2 is way off

[E--ly]

Why is the stride length and distance always way off if my charge 2 Fitbit has GPS? 

[RicardoFitbit]

Hi @E--ly thanks for your post, I'm happy to answer your inquiry and give you a warm welcome to our Community Forums.

Let me share with you that Fitbit devices 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. If your Fitbit device uses GPS and you track 1 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. However, 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.

I'll be here if you need anything else.