Fitbit and 'Track Exercise' give different readings

[Maz403]

I have recently started using the track exercise option on my iPhone to map my walks. The distance tracked by this does not match that on the Fitbit zip - for instance walk yesterday showed as over 7 miles on track exercise but only 5 on zip. I ran another tracker , which also used gps, at the same time and it agreed with the 7 miles.
Concerned now that unless I use the tracker every time I am getting an inaccurate measure. Any suggestions welcomed. Thanks

[Baltoscott]

@Maz403 -- you can adjust the stride length on the fitbit app to get more accurace distance tracking from your zip. The GPS used by the fitbit app on your phone will generally be more accurate, though.

[RobertoME]

Hi there @Maz403, good to see you around. 

@Baltoscott is right about the accuracy of the GPS. Usually the distance recorded by your Zip wont necessarily will be inaccurate. Is just that it works different that a GPS does.

Your Zip calculate distance by multiplying your walking steps and walking stride length. (This is similar when you are running). This will not necessarily match a pre-measured distance, nor will it show exactly what a GPS device will show. So to get better numbers for your distance if you are only using the Zip, you can adjust your stride length as was recommend before by @Baltoscott.

See you arond and stay awesome fellows.