Open your GPX (or TCX, KML) track.
Check the drawing of the route.
Press Convert and upload the .fit file to your training app.
Yes. The points are given times one second apart, so apps accept it, but pace and speed won't be meaningful.
For a route to follow, import the GPX itself into Garmin Connect as a course. FIT files made here are recorded activities.
No. Everything happens inside your browser, on your own device. The site's security settings stop the page from sending your files anywhere.
Yes. No sign-up, no daily limit and no watermark.
Yes, in Safari, Chrome and other modern browsers. You can open files from the Files app or your downloads, and save the results back.
Customer lists, contacts, bank exports and the routes you run from home stay on your phone or computer from start to finish.
How it stays private100 converters for the files people use every day.