Do you need a FIT file at all?
Often you do not. Several watch and bike computer apps import a GPX directly, so check your brand below first. Convert to FIT when a device, app or workflow asks for that format.
Menu names checked in November 2026. Apps change them, so yours may differ slightly.
Garmin
Garmin owners report that the course import on the Garmin Connect website takes GPX and TCX but refuses FIT. If you use Garmin Connect, import your GPX as it is, from Courses under Training and Planning. A FIT course is for copying to the device by USB.
Wahoo
For ACE, BOLT 3 and ROAM 3, the Wahoo app imports FIT, GPX and TCX route files, so a GPX works without converting. Older ELEMNT, BOLT and ROAM units import through the ELEMNT app.
COROS
COROS documents GPX for routes, so keep your GPX. Open it on your phone, choose the COROS app and tap Save. The route goes to your Route Library on the Explore page.
Polar
Polar Flow imports GPX or TCX, up to 25 MB, and does not list FIT. On the Flow website, click Favorites, then Import route, and sync with FlowSync. Long routes are compressed to 500 or 1500 waypoints, depending on the model.
Suunto
In the Suunto app on iPhone, keep your GPX: on the map, tap the plus icon, choose Import route (.gpx), pick the file and save it to your library.
How it works
Upload
Choose a GPX with a track or a route.
We build the course
Every point of the GPX goes into the course in order, with the distance along the route and its elevation if the GPX has one.
Download and test it
One .fit downloads straight away. Load it on your device and check it before you rely on it.
What is a FIT course file?
FIT is the binary format Garmin created for sports devices. A FIT course is a route to follow: a list of points with distance and elevation. A FIT activity is the opposite, a recording of something you already did, with heart rate, power and the real times. Both end in .fit, and they are different files.
What goes into the course
Kept
Every point of your track or route, in order, with the distance along it and the elevation if your GPX has it. The line is not simplified or re-routed.
Left out
Waypoints, stop names, turn instructions, sensor data and any times in your GPX.
- A course needs a time for every point, so we work them out at a steady 20 km/h or so (12 mph). A feature that races you against the course, such as a virtual partner, will use that speed.
- If your GPX has both a track and a route, the track is used.
- Several tracks are joined in order into one course, so any gap between them becomes a straight line.
- The name stored in the course is cut to 15 characters at most. The file name keeps the full one.
No turn-by-turn directions
Turn prompts in a FIT course are stored as separate course points, and this tool does not write any. You get the line and the distance. Some devices may work out guidance of their own from a line, and we cannot say which ones or how well. Plan to follow the line on the screen.
How to put the FIT course on your device
Garmin, by USB
Connect the device to a computer and copy the .fit into the Garmin/NewFiles folder. Eject it and unplug it, and it should then appear under Courses. This comes from Garmin users rather than a Garmin manual, and not every model behaves the same.
Wahoo ACE, BOLT 3 and ROAM 3
Open the .fit on your phone, choose the Wahoo app and confirm the import. Your phone needs an internet connection for this. Then, in Explore, My Collection, My Routes, choose Send to ELEMNT with the computer paired and connected.
Test it before you ride
We build the file to the FIT course layout that Garmin publishes, and we do not promise that it will load on any particular model. Load it at home, check that the line and the distance look right, and try a short stretch before you depend on it on a long day out. Devices have their own limits on course length and number of points, and this tool keeps every point of your GPX.
Files that will not give you a course
Waypoints only
A GPX with pins and no track or route has no line to follow. You will see an error and it does not use a conversion.
Files that are not GPX
KML, KMZ and .fit files are refused here, and that does not use a conversion either. Convert them to GPX first.
More tools for your route
- Check your GPX on a map first with the free GPX viewer.
- Turn a recorded .fit activity into a GPX.
- Merge several GPX files into one before you convert.
Frequently asked questions
How do I convert a GPX file to FIT?
Upload the .gpx file in the tool above and click Convert. A .fit course file downloads in a few seconds.
Will the FIT course give me turn-by-turn directions?
No. The file holds the line, the distance and the elevation, with no turn cues. Any guidance has to come from your device.
Can I import the FIT course into Garmin Connect?
Garmin owners report that its course import takes GPX and TCX, not FIT. If you use Garmin Connect, import your GPX as it is. The FIT file is for copying to the device by USB.
Why do the times in the course look wrong?
They are made up. A course needs a time for every point, so we work them out at a steady 20 km/h or so and ignore any times in your GPX.
Is the GPX to FIT converter free?
You can start for free: each month you get 2 free conversions with a free account, or 1 without one. Pro Lifetime is a one-time payment for unlimited conversions in both directions.
Do you keep my file?
No. The file is sent to our server, read once to build the course and not stored. We keep no copy of the file or the route.