Merge your activities. In seconds.
FIT, GPX, TCX – heart rate, power and laps are preserved. Your files never leave your device.
Processed locally – no uploadHow to check this
Drop files or choose · FIT, GPX, TCX · stays on your device
Garmin
Open the activity in Garmin Connect, use the gear menu, and download the original. That file is FIT.
Strava
Open the activity, then the menu, and export the original. ActivityMerge joins FIT. GPX and TCX come later.
Other devices
Export the recording as FIT when the device or app offers it. Drop both parts here.
One file is not enough yet. Add the second part of the same recording.
Route
Chart
- Upload the file to Strava or Garmin. Guide
- Delete the originals. Kudos on those activities are lost.
Donations are not connected yet. No payment provider is loaded.
One file again
Two recordings become one activity, with the pause still visible.
Sensors stay
Heart rate, power, cadence, altitude, temperature, GPS, and laps are copied.
Nothing is uploaded
The work happens in this browser. You can check that on the privacy page.
Questions
Do the files leave this browser?
No. Parsing and merging run on this device. There is no upload.
Which file can I download?
The merged file is FIT. GPX and TCX can be dropped, and this version tells you they are not merged yet.
What happens to the pause?
By default the gap stays a pause. Elapsed time includes it. Moving time does not.
Are heart rate and power kept?
Yes. Record channels, laps, and the primary device are copied. Developer fields are copied when their bytes are known.
Is ActivityMerge part of Strava or Garmin?
No. It is an independent tool. You export there, merge here, and upload the result yourself.