What is a GPX file, and what opens it?

What is inside one

Open a GPX in a text editor and you see XML: nested tags, readable words, and a great many numbers. The numbers are your coordinates. A single track point looks roughly like a latitude and longitude attribute, with an elevation in metres and a UTC timestamp as child elements. A day hike might contain a few thousand of these.

The format defines three kinds of thing, and mixing them up causes most of the confusion people have with GPX:

• A track is where you actually went — an ordered list of recorded points, usually with timestamps. This is what a recording app produces.
• A route is where you intend to go — a smaller list of turn points meant to be navigated, without timestamps.
• A waypoint is a single named place, unconnected to any line: a trailhead, a water source, a parking spot.

A file can contain any combination of the three. When a service says "this GPX has no activity data", it usually means you gave it a route where it wanted a track.

What opens a GPX file

On iPhone and iPad

iOS has no built-in GPX viewer, so tapping one in Files or Mail generally offers a share sheet instead of a preview. Any app that declares support for the format — recording apps, mapping apps, planning apps — will appear there and can take it in. TrailCam can import an existing GPX file.

On a computer

Google Earth Pro opens GPX directly and is free. QGIS handles it as a proper GIS layer if you want to do real analysis. GPX Studio and similar browser tools let you view and edit a track without installing anything. A plain text editor will always show you the raw contents, which is the fastest way to check whether a file is actually empty.

Online services

Strava, Garmin Connect, Komoot, AllTrails, Gaia GPS and most others accept GPX uploads. This is the practical reason the format matters: it is the common currency between them.

Why the format has lasted

Because it is boring, in the best sense. It is text, it is open, it is simple enough to parse in an afternoon, and it does not depend on any company. Formats that survive twenty years tend to have all four properties. Newer formats such as FIT are richer and much more compact, but they are binary and tied more closely to specific device ecosystems; GPX remains the one you can be confident will still open.

The practical consequence for anyone recording outdoors is simple: whatever app you use, make sure it can produce GPX. That single capability is what stops your history from being trapped.

Common problems

• The file opens but the map is empty — the GPX probably contains only waypoints, or a route rather than a track.
• Times are hours off — GPX timestamps are UTC; the viewer applies its own timezone.
• The file will not import — check the extension is still .gpx and that an email client did not rewrite it as plain text.
• The elevation profile looks like a saw blade — that is normal raw GPS elevation noise, not damage to the file. Most viewers smooth it before display; some do not.