GpxFix Blog

TCX to GPX: Why Convert a Garmin Training Center File and How It Works

By Roy Lachica on August 22, 2026. Last updated August 22, 2026.

You exported your activity and got a .tcx file instead of the .gpx a tool or website is asking for. TCX and GPX both describe a workout track, but they are not interchangeable, and a fair number of upload forms, route planners, and analysis tools only accept GPX. Here is what a TCX file actually is, why you end up with one, and what you gain by converting it.

What is a TCX file

TCX stands for Training Center XML, a format Garmin introduced for its Training Center desktop software. It organizes a workout as activities, laps, and track points, and it natively carries heart rate, cadence, speed, and power alongside position and elevation. Garmin Connect, and a number of older Garmin devices and third-party platforms, still offer TCX as an export or native format.

What is a GPX file

GPX, GPS Exchange Format, is a more universal, lighter weight standard focused primarily on tracks, routes, and waypoints, latitude, longitude, elevation, and time. Heart rate, cadence, and power are not part of the core GPX schema, they are added through a Garmin extension namespace (gpxtpx:TrackPointExtension) that most, but not all, platforms understand. GPX is the format most mapping tools, route planners, and fitness sites expect by default.

Why convert TCX to GPX at all

• Wider compatibility: many route planners, mapping tools, and community upload forms only accept GPX, not TCX. Converting once saves you from hitting a rejected upload later.
• Easier to repair: tools built for fixing GPS errors, missing time gaps, and elevation problems overwhelmingly work on GPX, since it is the more common format for this kind of processing.
• Simpler structure for editing: if you ever need to open the file, trim it, or inspect it by hand, GPX's flatter structure is far easier to read than TCX's nested activity and lap hierarchy.
• Consistency across a library of files: if most of your workout history is already GPX, keeping everything in one format avoids having two different pipelines for viewing, comparing, or archiving your activities.

What you keep, and what changes, during conversion

A proper TCX to GPX conversion preserves the data that matters for training: latitude, longitude, elevation, timestamps, heart rate, cadence, and power where present, along with lap boundaries. What changes is the container structure, TCX's Activities and Laps become a GPX track with one or more track segments, and sensor data is written into the standard Garmin trackpoint extension so downstream tools can read it. A conversion that quietly drops heart rate or power to save space defeats the point, the goal is a like-for-like GPX, not a stripped-down one.

How GpxFix handles TCX files

You do not need a separate conversion step. Drop a .tcx file into GpxFix the same way you would a .gpx or .fit file, GpxFix detects the Garmin Training Center format automatically, converts it to GPX behind the scenes, and reports how many track points were converted, all before any of the GPS, elevation, or heart rate fixes run. From there you can crop, repair, or clean the file exactly as you would any other upload, and download a standard GPX at the end.

When TCX might actually be what you want

If your workflow revolves entirely around Garmin's own ecosystem and the tool you are sending the file to explicitly wants TCX, for example because it relies on the Lap structure for interval analysis, there is no need to convert. Conversion is worth doing specifically when the destination expects GPX, or when you want the file in the more broadly supported format for future use.

Frequently asked questions

Does converting TCX to GPX lose heart rate or power data?

It should not, provided the converter writes sensor values into the standard GPX trackpoint extension rather than discarding them. GpxFix preserves heart rate, cadence, and power through the conversion.

Can I upload a TCX file straight to GpxFix without converting it first?

Yes. GpxFix recognizes TCX files automatically on upload and converts them internally, there is no separate conversion step to run first.

Is GPX or TCX better for GPS error fixing?

GPX, since it is the format most repair and analysis tools, including GpxFix's own GPS spike and gap fixing tools, are built around. Converting early keeps the rest of your workflow simpler.

Have a TCX file you need cleaned up or converted? Open it in GpxFix and it will be handled automatically. Related reading: getting a GPX file onto your Garmin watch.