How to Convert a FIT File to GPX or GeoJSON for Free

FIT files are everywhere in the GPS fitness world — every Garmin watch, Wahoo cycling computer, and most Suunto and Polar devices record activities in this format by default. The problem is that almost nothing outside the Garmin/Wahoo ecosystem can read it directly. This guide explains what a FIT file actually is and how to convert one to GPX or GeoJSON for free using the GeoDataTools FIT converter — no account, no upload, nothing installed.

What Is a FIT File?

FIT (Flexible and Interoperable Data Transfer) is a compact binary file format developed by Garmin (via the ANT+ Alliance) for recording activity data from GPS sports devices. Unlike GPX, which is XML text, FIT is a byte-packed binary protocol — every activity, every recorded data stream (GPS position, elevation, heart rate, cadence, power, temperature), and every device setting has its own compact binary message format. That compactness is exactly why device manufacturers use it: a multi-hour ride recorded every second takes a fraction of the storage a GPX file would.

The tradeoff is that a FIT file can't be opened as text, inspected in a text editor, or read by most GIS and mapping software without first being decoded. That decoding step is what a FIT parser does.

Why Convert FIT to GPX or GeoJSON?

GPX and GeoJSON are both open, well-supported formats that essentially everything can read:

• GPX is the universal format for GPS devices — Garmin, Wahoo, and virtually every route-planning app (Komoot, AllTrails, RideWithGPS) will import a GPX file even if they can't read the original FIT file from a different manufacturer's device.
• GeoJSON is the standard for web maps and GIS tools — Leaflet, Mapbox GL JS, QGIS, and PostGIS all read it natively, with no plugin or conversion step needed.

Converting gets your activity data out of a single-vendor binary format and into something you can actually use elsewhere.

How to Convert a FIT File Online

• Step 1 — Open the tool. Go to the FIT to GPX / GeoJSON converter in any modern browser.
• Step 2 — Upload your FIT file. Drag and drop your .fit file or click to browse. The file is read and decoded directly in your browser.
• Step 3 — Review the extracted track. The tool shows the number of GPS points found and the total distance, so you can confirm the file parsed correctly before downloading.
• Step 4 — Download. Choose GPX for GPS devices and route-planning apps, or GeoJSON for web maps and GIS software.

What Gets Converted — and What Doesn't

This tool extracts the core GPS track: latitude, longitude, elevation, and timestamp for every recorded point, combined into a single continuous route. That covers what you need to view the route on a map, measure distance, or check the elevation profile.

It doesn't carry over other data streams a FIT file can contain — heart rate, cadence, power, running dynamics, and similar sensor data. Neither GPX nor GeoJSON has a standard, universally-supported place to put those metrics inside a route file, so a straight FIT-to-GPX/GeoJSON conversion focuses on the geographic track rather than trying to force fitness metrics into a format that isn't built for them. If you need the full sensor data, Garmin Connect or Strava's own export tools preserve that context better than a generic format conversion can.

Where to Find Your FIT Files

• Garmin Connect: Open the activity, click the gear icon, and choose Export Original to download the raw .fit file exactly as recorded by the device.
• Wahoo: Activities sync automatically to the Wahoo Fitness app and connected platforms; the original FIT file can be exported from the activity detail view.
• Suunto: Export from Suunto app under the activity's share/export menu.
• Direct from device: Most Garmin and Wahoo devices also store raw .fit files on their internal storage under a /GARMIN/ACTIVITY/ or similar folder when connected via USB.

Your Activity Data Stays on Your Device

FIT files can carry detailed personal data — GPS tracks that reveal home addresses and daily routines, heart rate, and other health-adjacent metrics. Like the rest of GeoDataTools, this converter decodes the binary file entirely client-side in JavaScript. Nothing is uploaded, logged, or stored anywhere. If you want to check the resulting route's elevation profile next, the elevation profile viewer works the same private, browser-only way.