JSON (GeoJSON)

phpGPX outputs JSON in GeoJSON format (RFC 7946). Both JSON_FORMAT and GEOJSON_FORMAT produce identical GeoJSON output.

Saving to file

PHP

$file->save('output.json', phpGPX::JSON_FORMAT);
// or equivalently:
$file->save('output.geojson', phpGPX::GEOJSON_FORMAT);

Getting JSON as string

PHP

$geoJsonString = $file->toJSON();

Structure

The output is a GeoJSON FeatureCollection:

JSON

{
    "type": "FeatureCollection",
    "features": [
        {
            "type": "Feature",
            "geometry": {
                "type": "Point",
                "coordinates": [17.054, 48.157, 134.0]
            },
            "properties": {
                "name": "Waypoint 1",
                "ele": 134.0,
                "time": "2024-01-15T07:00:00+00:00"
            }
        },
        {
            "type": "Feature",
            "geometry": {
                "type": "MultiLineString",
                "coordinates": [
                    [[17.054, 48.157, 134.0], [17.055, 48.158, 136.0]]
                ]
            },
            "properties": {
                "name": "Morning Run",
                "stats": { "distance": 1250.5 }
            }
        }
    ],
    "properties": {
        "metadata": { "name": "My Track" },
        "creator": "phpGPX/2.0.0-alpha.2"
    }
}

Geometry type mapping

GPX element	GeoJSON geometry
Waypoint (<wpt>)	Point
Route (<rte>)	LineString
Track (<trk>)	MultiLineString (one line per segment)

Coordinate order

GeoJSON uses [longitude, latitude, elevation] order, which is different from the GPX lat/lon order. phpGPX handles this conversion automatically.

DateTime format

All datetime values are serialized as ISO 8601 UTC strings (e.g. 2024-01-15T07:00:00+00:00). This is the industry standard for GeoJSON and data interchange formats. If you need a different format for display, transform the dates on the consumer side.

Pretty printing

Control JSON formatting via Config:

PHP

use phpGPX\Config;

$gpx = new phpGPX(new Config(prettyPrint: false));
$file = $gpx->load('track.gpx');
echo $file->toJSON(); // compact, single-line JSON

Using with Leaflet

JavaScript

fetch('output.geojson')
    .then(r => r.json())
    .then(data => L.geoJSON(data).addTo(map));