How to reduce the number of points in a GPX track
Cutting down the number of points in a GPX track is usually called simplifying it, and it is a job for separate GIS or GPS software, not something built into a recording app. Done with a proper simplification tool, it keeps the line looking the same on a map while needing far fewer points to draw it. Done crudely — by deleting every few points on a fixed schedule — it can round off corners and flatten exactly the sharp turns that made the route what it was.
The short answer
The standard way to reduce points in a track is a simplification algorithm — the Ramer–Douglas–Peucker algorithm is the one most GIS and GPS tools actually use — which keeps points where the line changes direction and drops points along stretches that are already close to a straight line. A tight switchback keeps most of its points because the line is turning sharply there; a long straight fire road loses most of its in-between points because a handful of them describe that stretch just as well as hundreds do. This lives in general-purpose tools built for editing geographic data, not inside the app that recorded the hike in the first place, because it is a one-off cleanup applied to a finished track rather than something that needs deciding while a hike is still being recorded.
Why anyone bothers with this
File size is rarely the actual reason. A GPX track is plain text, and even a long day out stays a fairly small file next to the photos and video clips a hike might also carry — the point count on its own is unlikely to make a file too big to email or upload. The more common reason is a limit on the receiving end: some import tools, older dedicated GPS units, or a specific step in a workflow cap how many points they will accept from a single track, and a densely logged file can simply be turned away. A secondary reason is how the line looks once it is drawn somewhere else — a very high point density can render as a slightly jittery or 'furry' line at certain zoom levels, and a simplified version can look cleaner without actually changing where the route went.
A careful simplification versus a crude one
It matters which method does the reducing. A real simplification algorithm looks at the shape of the whole line and keeps whichever points that shape actually needs, so a turn stays a turn and a straight stretch shrinks down to its endpoints. A crude approach — deleting every third or fifth point, say, or keeping one point per fixed distance regardless of what the line is doing there — treats every part of the track the same, whether it is turning sharply or barely moving at all.
- A fixed-interval deletion can shave the corner off a tight switchback, since it has no idea that particular point was the one holding the turn together.
- It can also thin out a short out-and-back stretch until the two directions of travel look like one blurred line instead of two, since nothing about a fixed schedule protects a point just because it happens to be where you turned around.
A proper simplification tool avoids both problems because it decides what to keep based on the actual shape of the track, not on a fixed rule applied blindly to every point regardless of where it falls.
What gets thinner along with the points
A GPX point usually carries more than just a position — a timestamp and an elevation value typically ride along with it — and removing a point removes all of that together, not just the spot on the map. A heavily simplified track has fewer timestamps left to work from, which matters if something downstream recalculates pace or moving time from the file rather than reading a total that was already saved. Elevation is affected too: a simplification pass built for a clean-looking line on a map is optimising for position, not for elevation, so small dips and rises that the original recording caught can get smoothed straight through if the points that captured them happen to fall on an otherwise-straight stretch of the route.
Where TrailCam fits in
TrailCam records a route at the density it actually walked and exports it as a standard GPX 1.1 file without thinning it first, so the export reflects the hike as recorded rather than a version that has already been reduced for you. If wherever you are taking that file needs fewer points than it arrived with, that is a separate step to run afterward with a tool built for simplifying tracks, not a setting inside TrailCam itself. GPX export is part of the optional TrailCam Pro upgrade; the app itself is free to download.
Questions
- Does reducing the number of points change the distance a track shows?
- A well-simplified track keeps its shape close enough that distance barely moves, since the algorithm is choosing points specifically to preserve the line. A crude, fixed-interval reduction can shift distance slightly more, because it can cut corners the careful method would have kept.
- Can a hiking app simplify a track for me before I export it?
- That depends on the app, but it is generally a separate job handled by GIS or GPS-focused software built for editing tracks, rather than something a recording app does automatically on export. A GPX file exported at full density can always be simplified afterward with a tool made for that.
- Is there a point count where a GPX track is definitely "too many points"?
- Not a universal one — it depends entirely on the limit of whatever tool or device the file is headed to. A track that one import tool accepts without complaint can be too dense for an older GPS unit or a different workflow with a lower cap.
Recording your own routes
TrailCam is an iPhone app that records your route with GPS, keeps video clips, photos and voice notes pinned to the spot where you took them, and exports the result as GPX 1.1 or CSV. It is free to download.