Trim a GPX file
Warm-up before the start line, a wrong turn, or a few minutes of GPS drift in the car park — trim it off. Drop your file, drag the two handles to bracket the part you want to keep, and download a clean GPX. It all happens in your browser.
Open the tool
Opens the GPX editor with the trim a gpx file tool selected. Your file stays on your device — nothing is uploaded.
Open the GPX trimmerHow to trim a gpx file
- Open your file. Drop a GPX (or FIT, TCX, KML, KMZ) into the editor — it's read locally, never uploaded.
- Set the keep range. Drag the start and end handles; the label shows the point index and distance at each edge, live on the map.
- Apply & download. Click Apply trim, then export the trimmed GPX from the Download menu. Undo is always available.
Formats & what's kept
- Input: GPX, FIT, TCX, KML, KMZ
- Output: GPX 1.1
- Preserved: Everything on the kept points — elevation, timestamps, heart-rate/cadence/power/temperature, multi-segment structure, waypoints and unknown extensions.
- Changed or dropped: Only the points outside the range you keep. The kept section is byte-for-byte faithful to the original.
A real example
You stopped your watch a minute late at a parkrun, so your 5 km shows as 5.3 km with a slow tail. Trim the last 40 seconds and the distance, average pace and elevation all recompute from the real finish.
| Before | After |
|---|---|
| 1,612 points · 5.31 km | 1,498 points · 5.02 km |
Try it yourself with a free sample GPX file — the numbers above are illustrative of a typical case.
Privacy
This edit runs entirely in your browser using the W3C File API — your file is never uploaded, and your original is left untouched (the editor works on a copy). This tool makes no network requests at all to do its job; only route planning and snapping, which this tool doesn't perform, would ever send coordinates to a routing provider.
Frequently asked questions
Does trimming re-calculate my stats?
Yes. Distance, duration, average and max speed, and elevation gain are all recomputed from the points you keep — so the trimmed file's metrics reflect the real activity, not the original.
Can I trim out a chunk from the middle?
The trimmer keeps one contiguous range. To cut a middle section, split the track at the two boundaries and keep the halves you want, or trim twice. A precise multi-range cut is coming with the point editor.
Will my heart-rate and cadence survive?
Yes — every Garmin TrackPointExtension value on the kept points is preserved exactly, and the metrics panel keeps showing HR/cadence/power/temperature.
Is my file uploaded to trim it?
No. Trimming runs entirely in your browser with the W3C File API. The file never leaves your device, and your original is untouched — the editor works on a copy.