What is a GPX file?

A GPX file is a plain text file that holds coordinates. GPX stands for GPS Exchange Format. Because it is an open format that no single company owns, almost every GPS unit, watch, phone app and route planner reads and writes one.

The file carries no map of its own. What it holds is a list of points describing a line someone rode or planned, plus the places they marked along the way. The roads and terrain under that line come from the device or the app you open the file in, which is why the same GPX file looks different in every one. That is the file emailed after a ride, downloaded from a ride report, and sent to a Garmin.

Why the file opens in Notepad#

The file is correct. A GPX file is structured text in XML. Neither Windows nor macOS ships an application that draws a GPX file on a map, so nothing on your computer is registered to open one.

The file still works everywhere else, so drop it into an app that draws it and the same file appears as a line. See how to open or view a GPX file.

Do not rename the extension, because the file is already correct as it is, and it holds no program code, so opening it cannot run anything on your computer.

TopoGrafix published GPX 1.0 in 2002 and GPX 1.1 in 2004. Both versions are public and free for anyone to build on, which is why a Garmin, a phone app and a route planner all read the same file.

The three things a GPX file can hold#

One file can hold all three at once, so a file can look like it failed to import when it landed under a list you were not watching.

Check all three lists before you send the file again. Look in the track list, the route list and the saved places list.

Which one do you want?#

Off pavement, use the track.

A route hands the connecting job to the device, and the device knows only the roads on its own map. Where the two-track someone sent you is missing from that map, the device works out a way around on roads it does know. What you follow is the device's detour rather than the ride you were sent, and where the roads it does know are paved, that detour is pavement. A track draws whether or not the device believes the road is there.

How a Garmin uses each one#

A route sent from INVIA arrives as a track, so it lists with the Garmin's tracks rather than in the trip planner or the route planner. Named places arrive among the saved places.

On many Garmin models an imported track is not drawn on the map until you open it and turn its map display on. An empty map after a transfer is a display setting rather than a failed send.

The track is on the Garmin. It is in the track list. The map is empty because the track's map display is off.

1. Open the track list on the Garmin.
2. Open the track.
3. Turn its map display on.

Work through all three lists before you decide the transfer failed, because a file that landed under a list you did not check looks the same as one that never arrived.

GPX against FIT, TCX and KML#

You do not need to convert a GPX file for a Garmin. A Zumo, Tread, Montana, GPSMAP, Oregon or eTrex reads a GPX file as it is, so there is nothing to convert. The advice to convert GPX to FIT first belongs to watches and cycling computers.

Your ride comes back off the Garmin as a .fit file#

The Garmin records in Garmin's own activity format even when you sent it a GPX file. Your ride is on the Garmin and complete, and only the format of the returning file has changed.

Import the .fit file the same way you import a GPX file, because INVIA reads activity files off a connected Garmin alongside its GPX tracks.

TCX does not import#

INVIA does not accept TCX yet, so the import is rejected and nothing from that file reaches your library. GPX, KML and Garmin FIT files all import, so save the line as a GPX file instead and it comes in.

What survives a KML import#

INVIA converts a KML file on the way in, which means you get a track and named places in your library rather than a copy of the original file.

The lines and points in the file import even when an overlay is skipped, so nothing you can ride is lost. Choose the route color again in INVIA after the import, because the styling in the KML file does not travel with it.

INVIA does not read a zipped KMZ file, so import a KML file instead. Choose a KMZ through Import and nothing from it reaches your library, because INVIA answers with a message naming GPX, KML and FIT as the formats it accepts. Drag a KMZ onto the map and nothing happens at all and no message appears, because the map picks up only the file types INVIA reads. Nothing in INVIA unzips a KMZ, which means the app cannot turn one into a KML for you, so the KML has to come from the program that produced the KMZ.

What a GPX file does not contain#

• No map. Coordinates only, so the roads, terrain and imagery under the line come from the device or the app that draws it.
• No guaranteed elevation or time. Both are optional, and a recording usually carries both while a planned line often carries neither, which is how software tells the two apart.
• No standard turn instructions. Some planners write machine cue points in as street addresses, so the import shows extra stops named after an address. INVIA removes those stops from a file loaded from your computer, and the line is unchanged.
• Nothing about surface, difficulty or access. The file cannot say whether a road is open, gated or legal for your machine, so a line on your screen is not proof of access.
• No sensor data as standard. Heart rate, cadence and power ride in optional extensions, and line color rides in an extension too.

INVIA states the same thing inside the app, because the limit applies to every line INVIA draws and not only to a file you were sent. The terms you agree to when you sign up make confirming legal access before you ride your own responsibility. Every route in the INVIA ride catalog carries the same note, to verify the route is open and legal for your vehicle before you ride.

Route color, and what a Garmin reads#

Route color is the color your line draws in on the device screen. GPX has no color field of its own, so color rides in an extension, written in one of two conventions.

A Garmin does not read a hex value.

A file carrying only a hex value draws in the device's default color. The route is on the Garmin and navigates normally, and only the color is wrong.

Send the file from INVIA and the color is right, because INVIA writes both values into one file and matches your route color to the nearest Garmin name by hue. A soft green stays green on a Montana 700-series instead of turning dark cyan, and a colored line is never matched to gray.

How to open or view a GPX file#

Open the file in something that draws it, and the screen of tags becomes a line on a map.

1. Choose Import on the Home page in INVIA. The file is saved to your library.
2. Or drag the file onto the map, which saves it to your library as well.
3. With a Garmin connected, choose From computer on the Device page. INVIA draws the file on the map and sends it across.

Do not rename the extension. The file is already correct.

An iPhone has no built-in application that draws a GPX file, so a file that arrives by message, mail or AirDrop shows no line. The iPhone holds the file and does not display the route, which means you share the file into an app that reads a GPX file to see the line.

Getting it onto a Garmin#

Which paths exist depends on the model, not on how new it is.

BaseCamp cannot see a Garmin that never mounts as a drive, so a Zumo XT, Tread, GPSMAP 67 or eTrex SE is not listed in BaseCamp at all. Use INVIA instead.

Garmin Express handles map and software updates, and it does not import routes, so it is not the tool for this job.

With no computer to hand, the Garmin Tread and Garmin Explore apps take a GPX file through the phone's share sheet.

INVIA is the only web application outside Garmin that sends files to a Garmin over the media transfer protocol, straight from a browser tab.

1. Connect the Garmin on the Device page in Chrome or Edge.
2. Choose From computer to load a GPX file from your disk. Choose From INVIA to take a saved route.
3. Choose Send to device. INVIA writes the file into the GPX folder your model reads.
4. INVIA re-reads the Garmin, so the file appears in the list and you can see that it landed.

On Windows, connecting any Garmin also needs INVIA Bridge, a small free background app that installs once. On a Mac nothing extra is needed.

Step by step, with the folder for every model.

How INVIA reads and writes GPX#

INVIA imports GPX, KML and Garmin FIT files, and it reads GPX tracks and recorded activities off a connected Garmin. TCX is not accepted yet.

What a file becomes is read from the file itself, because the points carry the evidence of how the line was made.

The import dialog shows what INVIA decided for each file, so you can change it there when the file is not what the points suggest.

A route built elsewhere stays whole, because INVIA does not cut it into segments, and its color is read back out.

INVIA writes standard GPX 1.1, with nothing proprietary added. A route sent to a Garmin travels as a track, so the Garmin draws the line you planned instead of recalculating it, and your named places travel with it.

A file loaded from your computer is rebuilt clean first, so cue points named after street addresses are removed while the line itself is unchanged. A file holding several tracks lands as one track file plus a saved places file named {file name} Waypoints.

What INVIA puts in a GPX file. How an imported file is classified.