TCX vs FIT vs GPX: What’s the Difference? (Which One Should You Use?)

TCX vs FIT vs GPX: what’s the difference? In practice: use FIT for Garmin-native compatibility, use GPX for universal GPS sharing, and use TCX when you need structured training data in XML (laps + metrics) or you’re exporting from platforms that produce TCX. If you want to inspect what’s inside a file before converting, open it in the TCX File Viewer or FIT File Viewer.

Choosing the right format can save you time—and prevent missing metrics after import.

TL;DR: which format should you use?

Your goal	Best choice	Why
Upload to Garmin / keep Garmin-native	FIT	Garmin’s preferred format; compact and rich in device metrics
Share a route/track with almost any app	GPX	Widely supported standard for GPS tracks/routes
Keep an XML workout file with structure (laps/trackpoints)	TCX	Human-readable XML; common export from fitness platforms
Open in spreadsheets for analysis	CSV	Easiest for Excel/Sheets (convert from TCX/FIT)

What is a FIT file?

FIT (Flexible and Interoperable Data Transfer) is a compact binary format used by Garmin and many fitness devices. FIT files often contain:

GPS (if recorded)
Heart rate, cadence, power (if recorded)
Device-specific fields (more detailed than GPX)
Structured data useful for training analysis

If you’re working with .fit files, start here:

What is a GPX file?

GPX (GPS Exchange Format) is an XML standard designed to exchange GPS data between tools and services. GPX is great for compatibility, but it can be limited for certain training metrics depending on how it’s generated.

Use GPX when you need maximum “it works everywhere” portability—especially for route/track sharing.

What is a TCX file?

TCX (Training Center XML) is an XML workout format originally designed for Garmin Training Center. TCX often includes structured workout concepts like activities, laps, and trackpoints.

If you’re working with .tcx files, start here:

Comparison: TCX vs FIT vs GPX (what you might lose)

Different platforms preserve different fields during export/import. This table is a practical guide (your mileage may vary by device and platform):

Data / feature	FIT	TCX	GPX
GPS track	✅	✅	✅
Laps/splits	✅	✅	⚠️ Sometimes missing
Heart rate	✅	✅	⚠️ Depends on extensions
Cadence	✅	✅	⚠️ Depends on extensions
Power	✅	✅	⚠️ Often missing
Device-specific diagnostics	✅	⚠️ Limited	❌
Human-readable	❌	✅	✅
Small file size	✅	❌	❌
“Works everywhere”	⚠️	⚠️	✅

Best format for common use cases

Best for Garmin

Prefer FIT when possible.\n+ If you only have a TCX export, convert it:
TCX to FIT Converter

Strava supports multiple formats, but for broad compatibility across apps:

Prefer GPX for routes/track sharing\n+ Converters you may need:
FIT to GPX Converter
TCX to GPX Converter

Best for spreadsheets / analysis

If the goal is Excel/Sheets analysis, convert to CSV:

How to inspect a file before you convert (recommended)

Before converting, check what’s actually inside your file:

If it’s a TCX: TCX File Viewer\n+
If it’s a FIT: FIT File Viewer\n+

This helps you avoid surprises like “no GPS data” (indoor workouts) or missing metrics.

Convert between formats (common paths)

TCX → FIT: TCX to FIT Converter
FIT → TCX: FIT to TCX Converter
TCX → GPX: TCX to GPX Converter
FIT → GPX: FIT to GPX Converter
TCX → KML: TCX to KML Converter
FIT → KML: FIT to KML Converter