Best Free FIT File Viewers to Browse Your Garmin Activity Data
Quickest option: no install needed
If you just need to glance at a file right now, The Ride Atlas FIT Viewer is the easiest starting point. Drop your .fit file onto the page and you get an interactive map trace, an elevation profile, and a summary of distance, time, and pace. No account, no upload prompt asking for your email.
Jumpshare also has an online FIT viewer, though it leans more toward displaying raw structured data than giving you a map-based view of your route.
Desktop apps: when you want to dig deeper
Browser tools handle a quick sanity check just fine. For anything more — comparing laps, checking power against elevation, or working without an internet connection — a desktop app is the better fit.
FitFileViewer
FitFileViewer is open source, runs on Windows, macOS, and Linux, and works completely offline. Open a file and you get an interactive map, time-series charts for speed, heart rate, elevation, power, and cadence, plus a raw data table that shows every field the file actually contains. Nothing uploads anywhere.
It’s built with Electron so the download is a bit hefty, but setup is straightforward. The GitHub page has ready-to-run installers for all three platforms.
GPXSee
GPXSee is leaner and supports a wider range of formats: GPX, TCX, FIT, KML, IGC, NMEA, and more. That breadth makes it useful if you’re dealing with files from multiple devices or apps, not just Garmin. It shows tracks on a map with graphs for elevation, speed, heart rate, cadence, and power. Available on Windows, macOS, Linux, and Android under the GPLv3 license.
GPXSee loads fast and stays out of your way. It won’t give you the deep data-table view that FitFileViewer offers, but for a clean visual overview it’s hard to beat.
What’s actually inside a FIT file
FIT (Flexible and Interoperable Data Transfer) is a binary format developed by Garmin, now used by most major fitness device makers. A single file can contain GPS coordinates, altitude, heart rate, cadence, power output, temperature, lap boundaries, and device metadata — all timestamped to the second. That’s why a generic media player or text editor won’t open one; you need something that understands the schema.
Garmin publishes the full FIT SDK on their developer portal if you want to write your own tooling or understand exactly what fields a particular device records.
Which one to actually use
For a one-off look: The Ride Atlas. Fast, nothing to install.
For regular analysis or offline use: FitFileViewer. More data, more control.
If you work with files from multiple GPS devices or formats: GPXSee. Lighter footprint, broader format support.