GPS exchange format (GPX)

GPX stands for GPS Exchange Format. It is an exchange format for GPS geodata and is based on the Extensible Markup Language(XML). GPX files essentially consist of the attributes waypoints (wpt), route (rte) and tracks (trk). For all three attributes, the geographic reference points are specified in longitude (lon) and latitude (lat) and are accompanied by elevation information.

While the longitude and latitude are given in kilometers with two decimal places, the altitude is given in meters. All indications are in powers of ten and not in degree minutes and degree seconds. They are therefore easier to read and interpret.

Beside these standard indications there can be introduced the date and the time according to ISO 8601 as tags, also comments, the declination, the names of the elements, the position calculations, Horizontal Dilution of Precision (HDOP), Vertical Dilution of Precision (VDOP) and Position Dilution of Precision( PDOP) and some other criteria.

GPX is an open file format that can be used license-free. It is used for the acquisition and storage of geodata, as well as for export and import into other geodata programs.