FIT File Viewer

What is a FIT File?

FIT (Flexible and Interoperable Data Transfer) is a compact binary file format developed by Garmin that has become the standard for GPS fitness devices. Use this free online viewer to open and inspect any .fit file without installing software.

FIT files are designed to be compact and efficient, making them ideal for resource-constrained devices like GPS watches. Unlike text-based formats like GPX or TCX, FIT files use a binary encoding that minimizes file size while supporting a rich set of data fields. You can learn more in the official FIT Protocol documentation.

History of the FIT Protocol

The FIT protocol was created by Garmin and first released in 2008 alongside their Edge cycling computers. Originally designed for cycling data, the format quickly expanded to support running, swimming, and multi-sport activities.

In 2011, Garmin opened the FIT SDK to third-party developers, allowing other manufacturers to adopt the format. Today, FIT files are used by major fitness brands including Wahoo, Suunto, COROS, and many others.

The protocol continues to evolve with new message types and fields added regularly to support emerging sensors and metrics like running power, muscle oxygen, and advanced cycling dynamics.

What Data is Stored in a FIT File?

FIT files contain a wealth of activity data organized into different message types:

• Session: Overall activity summary including total distance, time, calories, and averages.
• Lap: Split data for each lap or interval, useful for analyzing pacing strategies.
• Record: Time-series data points (typically every 1 second) with GPS coordinates, heart rate, speed, cadence, power, and altitude.
• Event: Timestamps for start, stop, pause, and other activity events.
• Device Info: Details about the recording device and connected sensors.
• HR Zones / Power Zones: Training zone definitions and time-in-zone data.

Compare Multiple FIT Files

This tool supports comparing up to 6 FIT files simultaneously. This is useful for:

• Watch Comparisons: Compare data from multiple GPS devices worn during the same activity to evaluate accuracy.
• Workout Progress: Compare similar workouts from different days to track your improvement.
• Route Analysis: Compare your performance on the same route across different attempts.

Use Relative alignment to compare workouts from different days (aligns start times). Use Absolute alignment when comparing data from the same activity recorded by multiple devices.

How to Download FIT File from Garmin Connect

Follow these steps to export and download your FIT file from Garmin Connect:

1. Log in to connect.garmin.com
2. Navigate to Activities and select the activity you want to export
3. Click the gear icon (settings) in the top right corner of the activity
4. Select "Export File" to download the original FIT file
5. A .zip folder (containing the FIT file) will download to your device
6. Open the .zip file to access the FIT file

See Garmin's official export guide for more details.

How to Export FIT File from Strava

Follow these steps to download your original FIT file from Strava:

1. Log in to strava.com (this must be done on the web, not the mobile app)
2. Go to Your Profile and click on the activity you want to export
3. Click the three dots (...) icon in the left sidebar under the activity stats
4. Select "Export Original" from the dropdown menu
5. Your original FIT file will download automatically

Note: You can only export original files for activities you recorded. See Strava's export documentation for more options including bulk export.

Other Ways to Get Your FIT File

FIT files can also be obtained from these platforms and methods:

• Wahoo ELEMNT: Export from the ELEMNT companion app or connect your device via USB
• COROS: Export from the COROS app or connect your watch to a computer
• Suunto: Export from Suunto app or Suunto Movescount
• Direct from device: Connect your GPS watch or cycling computer via USB cable. Navigate to the Garmin/Activities or Activities folder to find your FIT files
• Zwift & TrainerRoad: Both platforms save FIT files locally and allow exports from their respective apps

Free FIT File Analysis

This FIT file viewer is completely free to use with no signup required. Upload your files, analyze your data, and compare activities without any cost or account creation.

Whether you need to review a single workout or compare multiple activities from different devices, this tool handles it all in your browser. No downloads, no accounts — just drag and drop your .fit files to get started.

Supported FIT File Sources

This viewer works with FIT files from any device or platform that produces .fit files, including:

• Garmin — Forerunner, Fenix, Edge, Venu, Enduro, Epix
• Wahoo — ELEMNT, KICKR
• COROS — PACE, VERTIX, APEX
• Suunto — All models with FIT export
• Zwift & TrainerRoad — Indoor ride and run files
• Strava — Original file exports from any activity

Privacy & Security

This FIT file viewer runs entirely in your browser. Your file is never uploaded to any server. All parsing and analysis happens locally on your device using JavaScript, ensuring your fitness data stays completely private.