GPX to GeoJSON converter

Turn a GPX into GeoJSON, the format web maps, QGIS and most mapping code read without a plugin. The file is converted on your device, so the track never passes through a server.

Your file is read on this device and never uploaded.

Then make it a film: Animate this route opens the track in Voyarc, which draws it on a real map and exports it as a video.

What it does, and what it does not

Writes a FeatureCollection with one Feature: a LineString of [longitude, latitude, height] positions.
Puts the times in properties.coordTimes, one ISO time per position, the convention togeojson uses.
Writes compact JSON on one line, because a long track is a large file already.
Waypoints are not written, and several tracks in the GPX become one LineString.

Questions

Why are the coordinates longitude first?

That is the GeoJSON standard, RFC 7946. GPX writes latitude first; the converter swaps them so every GeoJSON reader places the line correctly.

Can I put it on a Leaflet, MapLibre or Mapbox map?

Yes: add the file as a GeoJSON source or layer and it draws as a line. The times in coordTimes are ignored by the map and kept for your code.

How precise are the positions?

Every digit the GPX had is kept. Nothing is rounded, so the GeoJSON reads back to the same points.