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GPX file

Also called GPS Exchange Format, track file

What is a GPX file?

A GPX file is the standard open format for storing GPS routes, tracks and waypoints as plain text. It's what you download from a trail site and load onto a watch or phone, and almost every mapping app and GPS device reads it.

GPX file at a glance

Format
Open XML text
Holds
Tracks, routes, waypoints
Watch out for
Device point limits on long routes

What is inside a GPX file

GPX stands for GPS Exchange Format, and underneath it's XML: a text file listing coordinates in order, with optional elevation and timestamps. Because it's an open standard, a file exported from one app opens in nearly any other, which is why it's the lingua franca of trail navigation.

Tracks, routes and waypoints

It holds three kinds of thing and they're worth telling apart. A track is a dense breadcrumb of where something actually went, often thousands of points. A route is a sparser list of points describing where to go, sometimes with turn instructions. A waypoint is a single marked location: a spring, a junction, a campsite. Some devices handle all three well and some only follow tracks properly.

Getting one onto your device

The workflow is usually the same everywhere: find the route, download the GPX, and get it onto the device through the brand's app or by dropping it into a folder over USB. What varies is point limits. Some watches truncate very long tracks, so a hundred-mile route may need simplifying or splitting before it will load, and simplification tools in most mapping apps do this in a couple of clicks.

What this means when you're choosing

  • A track rather than a route, if you want the exact line someone walked
  • Whether your device caps the number of points, since dense tracks get truncated
  • That the file came from a source that actually walked it

The common mistake

Trusting a downloaded track as a plan

A GPX is a line someone recorded, not a statement that the route is open, legal, in season or within your ability. Check it against the land manager's own information before you follow it into anything committing.

Common questions

What's the difference between a GPX track and a route?

A track records where someone actually went, point by point. A route is a planned sequence of points describing where to go, usually with far fewer of them. For following a trail, a track is generally more faithful.

Why won't my GPX file load onto my watch?

Usually too many track points. Simplify the track in a mapping app or split it into sections, then try again. Occasionally it's a malformed file from an unusual source, which re-exporting through a mainstream app fixes.

Where this is defined

Where this comes up

Guides on Tom's Hiking where gpx file changes which product is right for you.

More in lighting and electronics

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Beam distance is how far a headlamp usefully projects light, quoted in meters. The industry standard measures it to the point where illumination falls to 0.25 lux, roughly the brightness of a full moon, which is dimmer than most people picture.

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A flood beam spreads light wide and close for camp tasks and slow ground. A spot beam concentrates it into a narrow cone that reaches further, for seeing ahead at speed. Most trail headlamps mix both, and the mix matters more than the lumen count.

Regulated output

A regulated headlamp holds a steady brightness as its battery drains, then drops off sharply near the end. An unregulated one fades continuously from the moment you switch it on, so it's dim long before the battery is actually empty.

Reactive lighting

Reactive lighting uses a sensor to measure reflected light and adjusts brightness automatically, dimming when you look at a map and brightening when you look down the trail. It extends battery life and can feel unpredictable at speed.

IP rating

An IP rating states how well a device resists solids and water, under the IEC 60529 standard. The first digit covers dust and the second water, so IPX4 is splash resistant, IPX7 survives brief submersion, and IP67 does both.

Breadcrumb navigation

Breadcrumb navigation draws your loaded route as a line on a blank screen with an arrow for your position, without any underlying map. It tells you whether you're on the route, and nothing about what's around you.

ABC sensor

ABC stands for altimeter, barometer and compass, the three sensors in an outdoor watch. The altimeter and barometer are the same pressure sensor read two ways, and the compass is a magnetometer that gives you a heading when you're standing still.

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