Convert TCX to KML

A TCX file from a Garmin device typically carries more than most people realize — heart rate, cadence, power, and full lap-by-lap structure alongside the route itself. None of that makes it into KML. KML is built for one job, rendering a path in Google Earth or a similar viewer, and its schema simply has no fields for sensor readings or lap boundaries — geometry and a timestamp per point are all it was ever designed to hold, so this conversion strips everything down to that before it writes the file. If your reason for converting is to look at where you went — flying through a route in Google Earth, checking the line against terrain, sharing a visual with someone who doesn't need the numbers — that's exactly what this produces, and cleanly. If you need the training data alongside a viewable route, this is the wrong direction: consider TCX to GeoJSON instead, which keeps heart rate, cadence, and power attached to each point (though it drops laps too, since GeoJSON has no lap concept either) and still opens in modern web-mapping tools. One structural note carried over from the GPX-to-KML conversion on this site: KML writes coordinates as longitude, latitude, elevation, reversed from TCX's own ordering, which is a property of the KML spec rather than anything this tool changes. Position, elevation, and per-point timestamps come through exactly. As with everything on FitFileHub, this happens entirely in your browser — no upload, no account — so a training route from a private location never has to touch a server just to become a KML file you can look at.