Wrong elevation on route creator

Me pasa lo mismo. Tanto en Garmin Connect Web como en Garmin Connect App

Same problem for me, if I create a new route or import a gpx the elevation is totaly wrong on Garmin Connect Web...

Same here.

Indeed. Just created a route which includes the first part of Alpe d'Huez. Between turn 19 and 16 Garmin Connect calculates over a distance of approx. 1km a total of 158m of ascend and 72m of descend. I know for a fact that there's no descending on that piece of road. To add to that, 158m of ascend is crazy, as that would mean an average gradient of 15.8%, and that's just not true. It's about 9% average. 
But this is just an example, a lot of places are just completely wrong. 

I am experiencing the same issue.
When I create a course or import it, the elevation is calculated to be roughly double.
Even if I re-import something that was previously imported successfully, the strange elevation is displayed.
The altitude in the ride log will still show the same values​as before.

stesso problema da 15 giorni!

Ho risolto scaricando un altra app: outdooractive

Same for me too! Any news of Garmin fixing it?

I've done some work on this...

A simple Route planned on garmin connect at my home town using garmin connect Here Maps, Google Maps or open street map all result ascent of 336m . The same route planned on Komoot, Strava, Outdoor Active gives ascent of 274m.

A 1 day route im planning in the alps garmin gives 5500m ascent vs 3600 on Komoot & Outdoor Active. So Garmin, its important you get this basic stuff correct, right?!?

The problem gets worse, if you plan the route on Outdoor Active and import it into Connect, the ascent initially looks ok (the same as was planned on Outdoor Active), but when you send it to your device (Edge840) then the ascent suddenly jumps up to what Garmin thinks it is.

The only positive thing is that you actually don't have to ascend the crazy amount of elevation Garmin thinks is in the route

But it sure is annoying that you can't rely on the number displayed in the data field "ascend remaining" to pace your ride.