Stitch multiple rides into a single seamless activity.

Drop both files into the combiner. They appear as draggable cards in the order you uploaded them. Drag to reorder if needed. Pick FIT (or GPX or TCX) as the output format and download. The merged file has the first activity's data followed by the second activity's data, with timestamps in the second file shifted to pick up one second after the first ended. Strava and Garmin Connect treat it as a single continuous activity.

Strava and Garmin both count each upload as its own activity, which wrecks daily streaks (a morning and evening commute look like two activities, but one was actually the whole day), distorts segment matching across a coffee-break gap, and produces messy training-log entries. Merging rolls multiple segments into one logical activity that displays and analyses as a single ride or run. Weekly totals are correct either way; what changes is how the activity feels in your log.

Collapsed to one second by default. The merged activity behaves as if you stopped the timer for an instant between segments rather than took a multi-hour break. The map will show a straight-line jump between the end of one segment and the start of the next (unless they happen to be at the same coordinate), which is honest about the cut. If you want the gap reflected as actual elapsed time, you would need to add stationary records via our [FIT Start Extender](/tools/fit-start-extender) between segments.

Yes - lat, lon, and altitude pass through every trackpoint untouched. Only timestamps in later files are shifted, by exactly enough to keep the merged sequence continuous. Your route on the map looks like you rode the first segment, then jumped instantly to where the second segment started, then rode the second segment - because that is what the merged file describes.

Yes - the tool accepts any combination of FIT, GPX, and TCX inputs from any device or platform. A Garmin Edge FIT followed by a Wahoo ELEMNT FIT followed by an Apple Watch GPX merges cleanly. The output is one file in your chosen format; the device_info messages of the first file get retained, and per-segment device differences are not surfaced (the merged file looks like one device recording continuously).

Yes - the merged FIT (or GPX/TCX) is fully valid and uploads cleanly. Strava treats it as a single activity. If the original separate files are already on your Strava account, the merged file may hit duplicate detection because it shares a start time with the first segment. Delete the original segments first or shift the merged file's start time using our [FIT Time Adjuster](/tools/fit-time-adjuster).

The combiner stitches files end-to-end in time - segment one finishes, segment two starts, the merged file plays them back in sequence. The [FIT Field Merger](/tools/fit-field-merger) overlays files in parallel - two devices recorded the same activity simultaneously, and you graft HR from one onto power data from the other. Combiner is for sequential merging; field merger is for simultaneous merging.

Yes - free, no signup, no upload. The merging runs entirely in your browser. Drop files, drag to order, download.