GPS Exchange Format

GPS Exchange Format

Filename extension	.gpx
Internet media type	application/gpx+xml and application/octet-stream
Initial release	2002
Latest release	1.1 August 9, 2004(2004-08-09)
Extended from	XML
Open format?	yes
Website	www.topografix.com/gpx.asp

GPS Exchange Format(GPX) is anXML schemadesigned as a commonGPSdata format for software applications. It can be used to describewaypoints,tracks,and routes. It is anopen formatand can be used without the need to pay license fees. Location data (and optionally elevation, time, and other information) is stored in tags and can be interchanged between GPS devices and software. Common software applications for the data include viewing tracks projected onto various map sources, annotating maps, andgeotagging photographsbased on the time they were taken.

Data types

Waypoints, routes and tracks recorded by GPS receivers.

A GPX file's main components includewaypoints,routes,andtracks:

• A waypoint (wptType) consists of theWGS 84(GPS) coordinates of a point and possibly other descriptive information.
• A route (rteType) is an ordered list of routepoints (or waypoints representing a series of significant turn or stage points) leading to a destination.In general, a route is used to describe directions for a journey which someone wants to take at some point in the future.
• A track (trkType) contains a series of waypoints what might also contain a timestamp. It is typically used to represent journeys which somebody has already completed or recorded.

In addition to the above, GPX files can also contain additional data. The minimum properties for a GPX file are latitude and longitude for every single point. Some vendors, such asHumminbirdandGarmin,use extensions to the GPX format for recording street address, phone number, business category, air temperature, depth of water, and other parameters.

Units

Latitude and longitudeare expressed indecimal degrees,and elevation in meters, both using theWGS 84 datum.Dates and times are expressed inCoordinated Universal Time(UTC) usingISO 8601format.

Sample GPX document

The document below is a sample GPX file which contains three waypoints which correspond to the locations of the German, Swiss, and Austrian parliaments.

<?xml version= "1.0" encoding= "UTF-8" standalone= "no"?>
<gpxxmlns="http://www.topografix.com/GPX/1/1"version="1.1"creator="Wikipedia"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.topografix.com/GPX/1/1 http://www.topografix.com/GPX/1/1/gpx.xsd">
<!-- Comments look like this -->
<metadata>
<name>Dataname</name>
<desc>ValidGPXexamplewithoutspecialcharacters</desc>
<author>
<name>Authorname</name>
</author>
</metadata>
<wptlat="52.518611"lon="13.376111">
<ele>35.0</ele>
<time>2011-12-31T23:59:59Z</time>
<name>Reichstag(Berlin)</name>
<sym>City</sym>
</wpt>
<wptlat="48.208031"lon="16.358128">
<ele>179</ele>
<time>2011-12-31T23:59:59Z</time>
<name>Parlament(Wien)</name>
<sym>City</sym>
</wpt>
<wptlat="46.9466"lon="7.44412">
<time>2011-12-31T23:59:59Z</time>
<name>Bundeshaus(Bern)</name>
<sym>City</sym>
</wpt>
</gpx>

See also

Concepts

• Point of interest
• OpenStreetMap,a collaborative project to create free editable maps using, among others, GPX traces
• Waypoint

File formats

• Exchangeable image file format
• Geography Markup Language
• KMLformat, compatible withGoogle Earth
• Shapefile
• TCX,Garmin Training Center XML

Standards

• NMEA 0183
• NMEA 2000

Software

• GPSBabel,used to upload/download/convert GPX files