GPX Editing, Without the Nightmare?

Chris Minerva's Avatar

Chris Minerva

27 Jul, 2021 05:16 PM


Here's what I'd like to be able to do and I want to know if the paid PC Desktop version of CalTopo will be able to support me before I drop the money on it. My Garmin watch routinely produces erroneous waypoints I want to be able to export either a GPX or FIT file from Garmin Connect, edit it to fix the problems, then re-import it back into Garmin Connect. Specifically, I want to be able to manually drag individual track points on a map to fix them and then export the "repaired" result. Equally critical, the result needs to be compatible for re-import into Garmin Connect. I've tried several other 3rd party tools that end up producing results that Garmin Connect then chokes on during the import thereafter.

When I try to edit an example track in the free version I get a warning that "this object has 5877 waypoints, editing disabled for performance reasons, edit anyway?". I would like to know if this is considered a performance issue only because of the latency associated with the free web browser interface? This amount of data should not be an issue for a modern PC/GPU. I have a similar issue with Google Earth, the rendering of which grinds to a halt even with a modern PC/GPU.

If I select "edit anyway" I get another warning that "this object's GPS time/elevation data will be lost on edit. edit anyway?". Is this data lost only for track points that are edited or for all track points in the file? I understand losing the elevation data when I drag a track point somewhere else but why lose the timestamp? It seems like the edited point should retain the timestamp and then when I re-import it back into Garmin Connect it can sync the elevation data during the import.

I've attached an example Google Earth screen shot of the types of errors I get and want to fix. Please let me know if the paid PC Desktop version of CalTopo will enable me to do this. I have also attached the associated GPX file as exported from Garmin Connect in the even you want to try it out on your end to confirm.

Thank you,
Chris Minerva

  1. 1 Posted by Chris Minerva on 27 Jul, 2021 05:18 PM

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    Also attaching the Garmin Connect FIT file in case it is useful.

  2. 2 Posted by Chris Minerva on 27 Jul, 2021 05:24 PM

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    I forgot to mention that when I try to use the (Chrome) browser version of CalTopo to edit this track the (rendering) performance completely grinds to a halt. It is completely unusable, often taking 10 seconds or more to respond to my mouse cues.

  3. 3 Posted by Tom on 28 Jul, 2021 01:41 PM

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    Fellow CalTopo user here.

    My guess is you might find it most useful and practical to use a separate application or tool that specifically focuses on editing recorded GPS tracks and files.

    Let's also see what CalTopop says.

    I'd also ask Garmin and other device providers for their insights. Please report back about what they say and what you learn.

    Here's are articles and that might be helpful, found using (See the Options section of the page.)

    I hope this is helpful.

  4. 4 Posted by Chris Minerva on 28 Jul, 2021 05:13 PM

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    Hi Tom,


    I have spent hours trying other 3rd party apps. They all generate results that are incompatible with re-import back into Garmin Connect. Garmin tech support is horrendous. They know it’s an issue, and has been one for over ten years, yet they don’t seem to care. They sell $600 watches instead of $600 solutions. GPS can sometimes get off and I don’t really blame the hardware, but don’t sell me hardware without a corresponding solution when something goes wrong in the data acquisition. Very frustrated with Garmin. Sorry for the rant.


    Hopefully CalTopo has some insight.




  5. 5 Posted by Tom on 28 Jul, 2021 06:10 PM

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    Might there be a way to use CalTopo or another tool rather than Garmin Connect or in addition to Garmin Connect, to eliminate the need to reimport an edited track into Garmin Connect?

  6. 6 Posted by Chris Minerva on 28 Jul, 2021 06:24 PM

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    I’m sure there is, but all my performance and trip stats for the past 10+ years are in Garmin Connect, so I’d essentially be losing my entire repository of fitness/training/movement stats by moving to something else.


    Note that CalTopo also clobbers the GPX file on edit. For example, if you move a track point it deletes all data for the point and then enters a new point with just the coordinates. I can understand deleting the elevation for the point, since I’ve moved it, but why delete the timestamp? Leave the timestamp and then fill in the correct elevation based on where I moved the track point.


    Essentially, there are a ton of 3rd-party tools that all seem to do their own thing and I haven’t found one that solves my problem. Just trying to shortcut a solution here by asking CalTopo directly.




  7. Support Staff 7 Posted by Meghan on 28 Jul, 2021 09:23 PM

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    Hi Chris,

    Thanks for reaching out! You brought up a lot in your help ticket so I will not my best to address everything.

    Currently most programs, including CalTopo, don't offer a way to maintain the timestamps while editing points because it makes the track less valid (even if you are potentially make it more valid by eliminating erroneous points). Have you tried splitting the line on each side of the errant point(s) and then rejoining it? This workflow would allow you to keep elevation and time stamp data. You can learn more about modifying tracks and lines on this page on our training site. I believe you should be able to import it back into Garmin Connect after that although I haven't tested it myself and therefore can't say definitively one way or the other. We may make improvements to editing tracks while preserving time and elevation data in the future although we are currently in the midst of several big projects at this time so it wouldn't be anytime soon.

    The browser does hand when editing a very long track such as yours for all the reasons that browsers hang. We are planning to eventually change some background things to help with that. In the meantime, if you want to edit a long track directly, it can be helpful to zoom in on the section you want to work on and make sure to wait for the browser to catch up after you edit a point before moving onto another point.

    And to clarify, changing to a desktop account will not improve the performance.

    Hope that helps clear things up!

  8. Meghan closed this discussion on 28 Jul, 2021 09:23 PM.

  9. Chris Minerva re-opened this discussion on 29 Jul, 2021 04:25 PM

  10. 8 Posted by Chris Minerva on 29 Jul, 2021 04:25 PM

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    Hi Megan,


    I understand your rationale. IMO if my track is messed up enough in the first place then it would be unreasonable for me to hold the edited version to any kind of rigorous standard of accuracy, but that’s a discussion for the brew pub I suppose. J


    I will try splitting the line and see how that works. I had avoiding trying to edit the track with Basecamp because the internet is saying it’s not supported anymore and I presumed it just wouldn’t work. After managing to get on the phone with Garmin tech support they convinced me to try to use Basecamp nonetheless and that eventually Garmin Explorer would handle this (but not yet). I did a few simple track point moves in Basecamp, exported the GPX, and it successfully imported into Garmin Connect and the data was correct. I thought I had found something that worked and I proceeded to spend another hour thoroughly cleaning up the track, re-exported from Basecamp, and then the import to Garman Connect failed.


    FWIW, Basecamp works just fine with no rendering lag with this example track which is over 5000 points. CapTopo still lags to the point of being unusable if I zoom all the way in first. If I resample the track down to 1000 points in CalTopo the rendering flows fine with no lag.


    Thanks for your help. I will continue to try to work with CalTopo and Basecamp for something that works reliably.




  11. Julie closed this discussion on 29 Jul, 2021 06:47 PM.

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