Elevation Gain is way too high

[jeffeb3]

I have done this climb a few dozen times. It is almost all uphill, with a few smaller down and back ups. My other fitness trackers (including previous fitbits, using the phone GPS) report about 1200ft of elevation gain total. That is pretty believable, looking at this graph and with the personal knowledge I have of this climb. But fitbit reported 3000ft. The min to max is about 750ft. There's no way I climbed from min to max 3.5x. This graph looks about right:

I also went around a lake on Sunday, and there was a little hill to the dam, but otherwise, it was level (it was following the shore of the lake) and fitbit reported 1100ft.

I live in an area where distance doesn't matter at all, and elevation is everything. I need a system that can get me closer than 200-300% of the right value.

Is there a way for me to get a log to send to an engineer so fitbit can fix this?

[Guy_ · Accepted solution]

Hi, @jeffeb3  - there is a known fault with elevation that Fitbit are aware of.

There is nothing you can do to fix it.

There are many posts on this in the Sense and Versa 3 forums.

[jeffeb3]

It is a real shame. It is about 15 mins of coding to add a low pass filter on the altitude measurements. It is a shame that is takes months to fix something so simple.

[Agrajag]

Months? It's been broken for YEARS.

And a low-pass filter is exactly what they need. What happens is that elevation, even on flat stretches have some inaccuracy to it, so it bounces up and down by a few feet every few seconds. Which means you'll "gain" hundreds of feets simply from standing still for an hour. It's utterly ridicolous.

And as you say, it's the kinda problem that is trivial to improve by code. Getting it 100% correct ain't possible (the fitbit can't know for sure whether the road is flat and the measurements are off by +-5 feet, or whether the road GENUINELY goes up and down by 5 feet) -- but it can get it a whole lot better than the current mess.

[Triletics]

@Agrajag if the filter wouldn't be able to solve the issue then another alternative is using elevation correction using GPS and high-resolution DEM maps. It's a solution used by some platforms (including Strava). So it's not like there is no way to fix the problem. There is rather no will to do so.