Deleting Multiple Courses from Garmin Connect

Years go by and still no solution to this one. So I decided to create a workaround.

1. Open your saved courses on Google Chrome: https://connect.garmin.com/modern/courses
2. Open the console panel in Developer Tools in Chrome. (Press Command+Option+J (Mac) or Control+Shift+J (Windows, Linux, Chrome OS) to jump straight into the Console panel.)
3. Copy paste this script to the console and hit Enter:

function foo() {
	var links = document.querySelectorAll('a[href="#delete-course"]')
	links[0].click()
	setTimeout(function() {
		document.getElementsByClassName("btn-primary")[0].click()
	}, 2000)
}
setInterval(foo, 3000)

The script goes through the list of your saved courses and deletes them one by one. Have a coffee. Enjoy.

If you do not want to delete ALL your courses just filter the ones you do want to delete to the list before running the script.

It can be done by clicking script, but can be done also with direct requests.

This lists own courses:

jQuery.getJSON(
    'https://connect.garmin.com/modern/proxy/web-gateway/course/owner/',
    function(j)
    {
        j.coursesForUser.forEach(
        function(c)
            {
                console.dir(c.courseId, c.createdDateFormatted, c.courseName, c.distanceInMeters);
            }
        );
    }
);

Deletion request can be added inside, but at first - add an if check to limit results, by date or name etc. and quadruple check if a search script returns correct results. Only then add deletion.

fetch('https://connect.garmin.com/modern/proxy/course-service/course/' + c.courseId,
{
    "headers": { "NK": "NT", "X-HTTP-Method-Override": "DELETE" },
    "method": "POST"
});

It is a problem, because my Garmin Fenix 6 watch says "maximum courses reached", so itsn't loading any new (starred Strava) routes, making navigation useless

That is not related to deleting multiple courses in Garmin Connect Web. 

To delete courses on the watch you will have to delete them on the watch.

Easiest and quickest to remove multiple courses is to connect your watch to a computer and remove the courses from the folder GARMIN\Courses

Thanks. But why would syncing TO the device be linked, but removing FROM the device, not be linked to connect? Via computer is a good workaround, but would expect an easier (app) interface... also to remove in Garmin Connect, as there is no option to select multiple

That is how it works. You can't remove routes on the device from Garmin Connect.

Why it works that way is probably because the route storage on the watch is limited so you must remove routes from the watch, but you can keep them all in Connect and push them to the watch when you need them again.

OMG, how can Garmin be this incompetent?! Still can't do multiple delete. Even on the website...

It's a big problem.