Wrong distance using GPS

[TilSos]

I always run 5 km on the same route and I track my running with GPS. The route is displayed exactly but sometimes the watch and the app only counts 4 km. Each displayed km is exactly 1.25 km in real. 

Moderator edit: Subject for clarity 

[RicardoFitbit]

Hi @TilSos, welcome to the Community Forums!

Thanks for bringing this to my attention and the details that were shared in your post. To better assist you with this, can you please let me know which Fitbit device are you using? When was the first time you experienced this and how many times since then? Which activities do you track using GPS? If you haven't already done so, I recommend you to check the information that's specified on our help article: How accurate is my GPS data? and Why isn't GPS working on my Fitbit device?. Please let me know how it goes.

Looking forward to your reply.

[TilSos]

Thank you for your answer. I use a Charge 2 and I first had this problem Saturday one week ago and again this Sunday. I track my jogging. 

[TilSos]