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FIT File Tools

A complete set of free, browser-based tools for working with Garmin FIT files. View, edit, crop, merge, convert, and repair activities. Your data never leaves your device — everything runs locally in your browser.

What are FIT file tools?

FIT file tools are utilities for opening, editing, converting, and fixing the .fit activity files written by Garmin, Wahoo, Suunto, and Hammerhead devices. The FIT format is compact and complete — it records every heart rate sample, every GPS coordinate, every power and cadence reading, plus device metadata and lap structure. The catch is that it is a Garmin-flavored binary format that most apps cannot read directly. This is where FIT file tools come in: parse the file, show you what is inside, edit out the bits you do not want, convert to another format, or repair a file that got corrupted on the way off the watch.

Which FIT file tool do I need?

Pick the tool by what you want to do with the file:

  • View the data — heart rate, power, GPS, lap splits → FIT File Viewer
  • Trim a warmup, cap a spike, fix a timestamp → FIT File Editor
  • Export to GPX, TCX, or CSV for use in Strava, Excel, TrainingPeaks, or mapping apps → FIT File Converter
  • Fix a corrupted file Garmin Connect rejected → FIT File Repair Tool
  • Combine multiple files from a split recording or multi-sport event → Combine FIT Files
  • Crop unwanted time off the start or end → Crop FIT File

Why browser-based FIT file tools

Every tool on this page runs entirely in your browser. Your FIT file is parsed, transformed, and downloaded without ever touching a server — your activity data, GPS coordinates, and device IDs stay on your machine. That makes these FIT file tools safe to use with private data and fast (no upload step), and it means they work offline once the page has loaded.

FAQ

What is a FIT file?

FIT (Flexible and Interoperable Data Transfer) is a compact binary file format created by Garmin for storing activity data from GPS watches and bike computers. A FIT file contains every recorded sample — heart rate, power, cadence, GPS, elevation — plus device metadata and lap structure. It is the standard export format from Garmin, Wahoo, Suunto, Hammerhead, and most ANT+/Bluetooth fitness devices.

Do these FIT file tools work with Garmin, Wahoo, Suunto, and other brands?

Yes. Anything that writes the standard FIT format works here — Garmin watches (Forerunner, Fenix, Edge), Wahoo ELEMNT bike computers, Suunto watches, Hammerhead Karoo, Coros, Polar Vantage, and Amazfit/Zepp after FIT export. The tools also handle the older Garmin .fit variants from pre-2018 devices.

Can I use these FIT file tools offline?

Yes. Every FIT file tool on this hub runs entirely in your browser using JavaScript. After the page has loaded, you can disconnect from the internet and the tools continue working. Your file is never uploaded to a server.

Which platforms accept the exported files?

FIT files exported from our tools work with Garmin Connect, Strava, TrainingPeaks, intervals.icu, Wahoo SYSTM, and any platform that accepts standard FIT. The converter additionally outputs GPX (universally readable by mapping apps), TCX (training platforms like TrainingPeaks), and CSV (for Excel or Google Sheets analysis).