How to open a .FIT file online
From file to map in seconds.
Open your .FIT file
Drag it onto the box or click to choose it from your device. It opens on your computer.
See it on the map
Points, lines and areas from your .FIT file appear on an interactive map. Click any feature to read its details.
Read the stats
Check distance, elevation gain and loss, the bounding box and a height profile linked to the map.
What is a .FIT file?
The common language of GPS devices.
A .fit file is a FITS (Flexible Image Transport System) astronomy image, the standard scientific data format used by telescopes, astrophotography cameras, and research archives since 1981. Open it with SAOImageDS9 or NASA FITS Liberator (both free). Note that .fit, .fits, and .fts all refer to the same format; renaming the file is enough if a tool insists on a specific spelling.
Programs that open .FIT files
| Full name | Flexible Image Transport System (FITS) image |
|---|---|
| Developer | FITS standard maintained by the IAU FITS Working Group / NASA |
| First released | 1981 (IAU standard) |
| Category | Maps & GIS |
| MIME type | application/fits |
| Signature | 53 49 4D 50 4C 45 ("SIMPLE = T" at offset 0) |
Related viewers
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Is my .FIT file uploaded anywhere?
No. Your .FIT file is read by your browser and never sent to us. Only the background map tiles are loaded from OpenStreetMap, which sees which map area you're looking at, not your data.
How is the elevation gain calculated?
We add up every climb between track points, ignoring tiny wiggles of less than 3 metres that come from GPS noise. That's close to what Strava and Garmin report; barometric devices may differ slightly.
How do I open a Shapefile?
A Shapefile is several files. Drop the whole .zip, or select the .shp, .dbf and .prj files together. With only the .shp you'll see the shapes but no attributes.
Can I convert GPX to KML or GeoJSON?
Use Export GeoJSON to save everything you see. GPX ↔ KML conversion is part of our upcoming converter.
My CSV has coordinates. Will it work?
Yes, if it has columns named like lat/latitude/y and lon/lng/longitude/x. Every row becomes a point with the other columns as properties.
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