5 Common FIT File Problems and How to Fix Them
Solutions for the most common FIT file issues: cropping, GPS drift, wrong activity type, format conversion, and viewing problems. Free tools and step-by-step fixes.
Having problems with your FIT files? Most issues can be fixed with the right tools. Whether you need to crop an activity, fix GPS data, or convert to another format, this guide covers the five most common FIT file problems and their solutions.
FIT files from Garmin, Wahoo, COROS, and other devices are generally reliable, but issues do occur. Here's how to solve them.
Quick Reference: FIT File Problems and Solutions
| Problem | Solution | Tool |
|---|---|---|
| Activity needs cropping | Trim start/end | FIT File Editor |
| GPS track is shifted | Apply offset correction | FIT File Editor |
| Wrong activity type | Change sport metadata | FIT File Editor |
| Need different format | Convert the file | FIT Converters |
| Can't view file contents | Use a viewer tool | FIT File Viewer |
Problem 1: Activity Needs Cropping
The Issue
Your recorded activity includes unwanted sections:
- Warm-up or cool-down that shouldn't be in the main workout
- Time spent waiting at a start line
- Walking to/from your car
- GPS lock delay at the beginning
- Forgot to stop recording at the end
Why This Happens
Most athletes have experienced pressing start too early or stop too late. Your watch records everything between those moments, whether you want it or not.
The Solution
Use the FIT File Editor to trim your activity:
- Upload your FIT file
- Find the "Trim Activity" section
- Adjust the start and end points
- Preview the trimmed activity
- Download the cropped file
The editor shows exactly what you're keeping, including:
- New duration
- Updated distance
- Time range after trimming
Learn More
For a complete guide, see How to Crop a FIT File.
Problem 2: GPS Track Is Shifted
The Issue
Your recorded route doesn't match where you actually went:
- Track runs parallel to the road, but offset by 20-50 meters
- Route shows you running through buildings
- Path is in the right shape, but in the wrong position
- Start/end points don't match your actual locations
Why This Happens
GPS drift has several causes:
| Cause | Description |
|---|---|
| Satellite geometry | Poor positioning of satellites overhead |
| Urban canyons | Buildings reflecting GPS signals |
| Tree cover | Forest canopy blocking signals |
| Ionospheric conditions | Atmospheric interference |
| Device cold start | GPS hadn't fully locked before starting |
The Solution
Apply a GPS offset correction using the FIT File Editor:
- Upload your FIT file
- Find "GPS Offset Correction"
- Enter the offset in meters (North/South, East/West)
- Use quick adjustment buttons for fine-tuning
- Watch the map preview update
- Download when the track aligns correctly
Tips for Getting the Right Offset
- Find a landmark you know (intersection, building corner)
- Measure how far off your track is from that point
- Apply that offset and check multiple locations
- Fine-tune with +10m adjustments
Learn More
See our detailed guide: How to Fix GPS Drift in FIT Files.
Problem 3: Wrong Activity Type
The Issue
Your device recorded the wrong sport type:
- Trail run classified as "Hike"
- Gravel ride marked as "Mountain Bike"
- Recovery jog detected as "Walk"
- Started with wrong activity profile by accident
Why This Happens
| Reason | Example |
|---|---|
| Speed-based detection | Slow trail run detected as hiking |
| Terrain confusion | Gravel vs mountain biking |
| Manual error | Started wrong activity on watch |
| Auto-detect failure | Unusual movement pattern |
The Impact
Wrong sport classification affects:
- Training load calculations
- VO2 Max estimates
- Recovery recommendations
- Activity categorization in platforms
- Annual statistics
The Solution
Change the sport type in the FIT File Editor:
- Upload your FIT file
- Find "Activity Metadata"
- Select the correct sport from the dropdown
- Choose a sub-sport if available (e.g., "Trail" for running)
- Download the corrected file
Available Sport Types
The editor supports all standard FIT sports:
- Running (Street, Trail, Track, Treadmill)
- Cycling (Road, Mountain, Gravel, Indoor)
- Swimming (Pool, Open Water)
- Hiking, Walking, Rowing
- Skiing, Snowboarding
- And many more
Learn More
Full guide: How to Change Activity Type in FIT Files.
Problem 4: Need a Different File Format
The Issue
You have a FIT file but need it in another format:
- Platform only accepts GPX files
- Want to share a route with someone using a different device
- Need CSV for spreadsheet analysis
- Want to view in Google Earth (KML format)
- Creating a workout file for Zwift or TrainerRoad
Why FIT Isn't Always Compatible
While FIT is the standard for Garmin and many other devices, some platforms and use cases require other formats:
| Format | Best For |
|---|---|
| GPX | Universal sharing, route planning apps |
| TCX | Training platforms, older software |
| CSV | Spreadsheet analysis, custom processing |
| KML | Google Earth visualization |
| ZWO | Zwift workout files |
| ERG | TrainerRoad and other trainers |
The Solution
Use our file converters:
| Conversion | Tool |
|---|---|
| FIT to GPX | FIT to GPX Converter |
| FIT to TCX | FIT to TCX Converter |
| FIT to CSV | FIT to CSV Converter |
| FIT to KML | FIT to KML Converter |
What's Preserved in Conversion?
| Data | GPX | TCX | CSV | KML |
|---|---|---|---|---|
| GPS coordinates | ✅ | ✅ | ✅ | ✅ |
| Timestamps | ✅ | ✅ | ✅ | ✅ |
| Elevation | ✅ | ✅ | ✅ | ✅ |
| Heart rate | ⚠️ Extension | ✅ | ✅ | ❌ |
| Power | ⚠️ Extension | ✅ | ✅ | ❌ |
| Cadence | ⚠️ Extension | ✅ | ✅ | ❌ |
Related Guides
Problem 5: Can't View FIT File Contents
The Issue
You want to see what's in your FIT file:
- Analyze workout data without uploading to a platform
- Check if a file is valid before uploading
- View detailed sensor data
- Troubleshoot an issue with your activity
- See data that platforms don't display
Why Standard Programs Can't Open FIT Files
FIT is a binary format—unlike text-based formats like GPX or CSV, you can't open a FIT file in a text editor or spreadsheet and make sense of it.
The Solution
Use the FIT File Viewer:
- Upload your FIT file
- View the interactive map with your GPS track
- See charts for heart rate, power, speed, elevation
- Explore lap and split data
- Check session summary statistics
- View device information
What the Viewer Shows
| Data Category | Information Displayed |
|---|---|
| Summary | Distance, time, averages, maximums |
| GPS Track | Interactive map visualization |
| Charts | HR, power, cadence, speed, elevation |
| Laps | Per-lap statistics and splits |
| Device | Model, firmware, sensor connections |
Privacy Benefit
Like all our tools, the viewer processes files locally in your browser. Your workout data is never uploaded to any server.
Bonus: FIT File Won't Upload
The Issue
A platform rejects your FIT file upload:
- "Invalid file format" error
- "Corrupted file" message
- Upload appears to succeed but activity doesn't appear
- Platform says file is too large
Possible Causes and Solutions
| Error | Likely Cause | Solution |
|---|---|---|
| Invalid format | Not actually a FIT file | Check file extension is .fit |
| Corrupted file | Download was interrupted | Re-export from device/Garmin Connect |
| File too large | Very long activity | Some platforms have limits; try shorter segments |
| Duplicate activity | Already uploaded | Check if it exists in your activities |
| Processing error | Platform issue | Wait and retry, or contact support |
Verifying Your File
- Open in FIT File Viewer
- If it displays correctly, the file is valid
- If it fails, re-export from the source
When to Contact Garmin Support
Some issues can't be fixed with editing tools:
Hardware Problems
- Consistent GPS issues across multiple activities
- Sensor not connecting despite proper pairing
- Device crashes during activity recording
- Battery drain causing incomplete recordings
File System Issues
- Activities not saving to device
- Files disappearing after sync
- Sync failures with Garmin Connect
Warranty and Replacement
If your device consistently produces bad data, contact Garmin support. You may have a hardware defect covered by warranty.
All-in-One: The FIT File Editor
For most FIT file problems, the FIT File Editor is your solution:
Features
| Feature | Problem It Solves |
|---|---|
| Trim/Crop | Remove unwanted portions |
| GPS Offset | Fix shifted tracks |
| Metadata Edit | Change sport type, name, time |
| Session Edit | Modify totals and averages |
| Record Edit | Fix individual data points |
Privacy
- 100% local processing
- No server upload
- No account required
- Files never leave your browser
Compatibility
- Works with Garmin, Wahoo, COROS, Suunto files
- Output compatible with all major platforms
- Valid FIT format guaranteed
Related Resources
Editing Guides
- How to Edit FIT Files - Complete editing guide
- How to Crop a FIT File - Trimming walkthrough
- Fix GPS Drift - GPS correction guide
- Change Activity Type - Sport type fixes
Understanding FIT Files
- Complete Guide to Garmin FIT Files - Format explained
- FIT vs GPX Format Comparison - When to use each
Tools
- FIT File Editor - Edit your files
- FIT File Viewer - Analyze your data
- FIT to GPX Converter - Convert formats
- FIT to CSV Converter - Export to spreadsheet