FitFileLab
Formats6 min read

How to open a .FIT file easily

You grabbed a .FIT file from your Garmin watch, Wahoo bike computer or Coros, and it just won't open: double-clicking does nothing, or shows a wall of unreadable characters. That's expected — the FIT format isn't a text file. Here's how to read it, view it and reuse it, without installing any software.

What is a .FIT file?

FIT (short for “Flexible and Interoperable data Transfer”) is the format Garmin created to record sport activity data. It's the native format of most modern GPS watches and bike computers: Garmin, Wahoo, Coros, Suunto, Bryton, Hammerhead and more.

Unlike GPX or TCX, which are text files (human-readable XML), a FIT file is a compressed binary format. That's what makes it compact and able to store a huge amount of data — GPS position, heart rate, cadence, power, temperature, elevation — but also completely unreadable if you open it in a text editor.

Why won't my .FIT file open?

Because no consumer app is associated with the .fit extension by default. When you double-click it, Windows or macOS doesn't know what to do. And even if you force it open in Notepad or Preview, you'll only see gibberish, because the content is binary-encoded. You need a tool that can decode the format.

Open a .FIT file right in your browser

The simplest method: use an online viewer that decodes FIT in the browser. You drop your file in and instantly see the route on a map, the elevation profile and every statistic — nothing to install, no account to create.

  1. 1

    Open the FitFileLab viewer

    Head to the visualizer tool. It works on desktop and mobile alike.

  2. 2

    Drop in your .FIT file

    Drag the file into the drop zone, or click to select it. Decoding happens instantly.

  3. 3

    Read your activity

    The map, elevation profile and stats (distance, duration, elevation gain, heart rate…) appear right away.

Open my .FIT file now

All processing happens in your browser: your file is never sent to a server. Your training data stays private, on your device.

Other ways to open a .FIT file

Depending on what you want to do, other options exist:

  • Garmin Connect — if the file came from a Garmin device, import it into the Garmin Connect app or site to see it in your history.
  • Strava — upload it as a manual activity to view it analysed alongside your other rides and runs.
  • Analysis software (Golden Cheetah, WKO5, Garmin Basecamp) — more powerful, but they need installing and are often for advanced use.
  • Online viewer — the fastest option when you just want a quick look without installing or signing in.

Convert a .FIT file to reuse it

Reading the file isn't always enough. To import it into another platform, share it or edit it, it's better to convert it to a more universal format. GPX is ideal for a route track; TCX keeps more training data (heart rate, cadence, power).

Convert a FIT to GPX

Here too the conversion is instant and 100% local: you get your converted file in one click, without it ever leaving your computer.

FAQ

Can I open a .FIT file without software?
Yes. An online viewer that decodes FIT in the browser lets you read the file without installing anything. You drop the file in and immediately see the map and statistics.
Why does my .FIT file show unreadable characters?
The FIT format is binary, not text. Opened in a text editor, it appears as a string of symbols. You need a tool that can decode the format to see its contents.
What's the difference between a FIT file and a GPX?
FIT is a compact, data-rich binary format (cadence, power, sensors), native to Garmin/Wahoo/Coros devices. GPX is a universal text format focused mainly on the GPS track, and accepted by almost every app.
Is my training data safe?
With a tool that processes everything in the browser, your file is never transferred to a server. It stays on your device, which keeps your data private.
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