100% private — files never leave your browser
FIT to KML Converter
Turn Garmin, Wahoo or COROS .fit activities into .kml files that open straight into Google Earth — track on the globe, elevation visible, and timestamps preserved so Earth's time slider can play the activity back. The conversion runs entirely in your browser; the file never leaves your device.
How to convert to KML
- 1
Drop your file
Drag a FIT, GPX, TCX, KML, KMZ or GeoJSON file onto the box above, or click it to browse. The source format is detected automatically from the file contents.
- 2
Wait a beat
The conversion runs in a background worker on your device. Typical activities finish in well under a second; even 50 MB files process without freezing the page.
- 3
Check the preview
Distance, duration, ascent and average heart rate are shown alongside a map of the converted track, so you can confirm nothing was lost before downloading.
- 4
Download
Click the download button and the .kml file is saved straight from memory. Nothing was uploaded, so there is nothing to clean up.
What is a FIT file?
FIT (Flexible and Interoperable Data Transfer) is the binary activity format created by Garmin and maintained by the FIT Coalition. Every Garmin watch, cycling computer and trainer writes .fit files, and brands like Wahoo, Zwift, COROS, Suunto and Bryton use it too. Because it is a compact binary format, a FIT file can hold a full season of second-by-second records — GPS position, altitude, heart rate, cadence, power, laps and sessions — in a fraction of the space the same data needs as XML.
The trade-off for that compactness is compatibility. FIT is a device format: desktop tools, older websites, GIS software and many coaching platforms either cannot open it at all or only import it through a vendor uploader. That is the moment most people go looking for a converter — and why this page exists. A faithful conversion preserves every sample your device recorded, including the extension channels (heart rate, cadence, power) that generic GPS formats often drop.
What is a KML file?
KML (Keyhole Markup Language) is the XML dialect born inside Keyhole — the software that became Google Earth — and later standardized by the OGC. It describes geographic features for display: placemarks, lines, polygons and images, each with the styling and folders that make a KML file read like a curated map rather than a raw data dump. Google Earth, Google My Maps and most desktop GIS packages open it natively.
KML is a mapping format, not a training format. Its geometry carries position and elevation well — and Google's gx:Track extension can even carry per-point timestamps for time-slider playback — but it has no concept of heart rate, cadence or power. Converting an activity to KML is the right move when the goal is showing a route to humans; when the goal is analyzing a workout, the fitness formats are the right home for the data.
Why put a workout into Google Earth?
Google Earth remains unmatched for showing a route to people who own no GPS gear. Drop a converted KML into Earth and the ride or run appears draped over real terrain — tilt the view and the switchbacks you suffered up stand out in 3D, with elevation from the file itself. For trip reports, club newsletters and 'this is what I did on vacation' moments, one KML link beats a screenshot of a training dashboard.
Because this converter writes Google's gx:Track when timestamps exist (and device recordings always have them), Earth's time slider works: drag it and watch the activity unfold point by point. That turns a static line into a replay — handy for analyzing where a race fell apart, or just for showing the family how the day went.
What carries over — and the honest limits
Position, elevation and timestamps convert point for point. Lap boundaries from the FIT file become separate KML placemarks, so an interval session shows up as ordered segments rather than one undifferentiated line. The KML is standards-compliant OGC KML 2.2 with the gx extension Google itself uses.
The limits come from the destination, not the converter: KML has no concept of heart rate, cadence or power, so those channels are dropped rather than approximated. If your real goal is analysis rather than display — or the audience needs the physiological data — convert to GPX or TCX instead; if the goal is 'look at this route in Earth', FIT to KML is exactly the right tool.
Your files never leave this browser
This tool — like every tool on this site — runs entirely as client-side JavaScript. The file you drop is parsed in a Web Worker on your own device, converted in memory and handed straight back to you as a download. There is no upload endpoint, no server-side conversion service and no temporary storage: you can watch the network tab in your browser's developer tools and confirm that no file bytes are transmitted anywhere.
That matters more with fitness data than with most files. A GPS track is a precise log of where you were, at what time, and how hard your heart was working — home address, training habits, favorite routes and race schedule all in one file. Keeping conversion on-device means third-party converters never get a copy of that log, and the tool keeps working identically on a plane, in a basement, or anywhere else without signal.
FIT vs KML at a glance
| Aspect | FIT | KML |
|---|---|---|
| Format type | Compact binary | Display-oriented XML (OGC standard) |
| Typical use | Device recording, training platforms | Google Earth / My Maps visualization |
| GPS + elevation | Yes | Yes |
| Timestamps | Yes | Yes (gx:Track) |
| Heart rate / power | Native | Not representable — dropped |
| Best for | Training analysis | Showing routes to humans in 3D |
Frequently asked questions
Save the .kml, then either double-click it (Earth associates itself with KML) or use File → Open inside Google Earth. The track appears in your Places panel, and if your recording has timestamps you can use the time slider at the top of the window to play the activity back.