Add timestamps to a GPX
A route you drew or exported has no times, so it won't show pace, moving time, or a clean speed graph. Give it a start time and an average pace and this tool writes a constant-speed timeline along the whole track — turning a plan into a timed GPX.
Open the tool
Opens the GPX editor with the add timestamps to a gpx tool selected. Your file stays on your device — nothing is uploaded.
Open the GPX timestamp toolHow to add timestamps to a gpx
- Open your route. Drop the untimed GPX (or FIT, TCX, KML, KMZ) into the editor — it's read locally, never uploaded.
- Set start time and pace. Pick a start time and type an average speed in km/h (e.g. 5 for hiking, 25 for cycling).
- Add times & download. Click Add times; timestamps are spread by distance so the pace is constant, then export the timed GPX. Undo restores the untimed file.
Formats & what's kept
- Input: GPX, FIT, TCX, KML, KMZ
- Output: GPX 1.1
- Preserved: Every coordinate, elevation value, sensor reading, segment and waypoint. Only the time on each point is written.
- Changed or dropped: This sets times on all points, so any existing timestamps are replaced by the constant-pace timeline — use it on untimed routes, not to tweak a real recording. It doesn't model stops, hills or real-world speed variation.
A real example
You planned a 12 km hike and want your watch to show a believable finish time. Add a 09:00 start at 4.5 km/h and the route reports a ~2 h 40 m duration with a sensible pace, instead of no time at all.
| Before | After |
|---|---|
| 3,000 points · no times | 3,000 points · 09:00 → 11:40 at 4.5 km/h |
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 it guess where I stopped or slowed down?
No — it assigns a constant pace, so times are spread evenly by distance. It's an honest, even timeline rather than a fabricated one that pretends to know your rest stops or climbs.
Will it overwrite the times in a real recording?
Yes. This operation sets a fresh timeline on every point, so run it on untimed routes. To fix a recording whose times are merely out of order, use the health check's timestamp repair instead.
Can I give it a total duration instead of a speed?
The page's tool uses a start time and an average speed, which together imply the duration. Leave the speed blank and it falls back to one second per point, which you can then treat as a placeholder.
Why would a route have no timestamps?
Routes drawn in planners, converted from KML, or exported as courses often carry only coordinates and elevation. Adding times lets pace-based tools, speed graphs and animated replay work.