Simplify a GPX track

Thin a dense track for a GPS that caps its points, a route planner that chokes on big files, or a map that should load fast. Move the slider, watch the count, and download: the file stays on your device the whole time.

Your file is read on this device and never uploaded.

Then make it a film: Animate this route opens the track in Voyarc, which draws it on a real map and exports it as a video.

What it does, and what it does not

Keeps the points the shape needs with the Douglas-Peucker method: a point goes only if the line without it stays within the tolerance you set.
Shows the point count live as the slider moves, and the line on the map follows.
Keeps the height and time of every point it keeps, and always the first and last point.
Points are only ever removed, never moved or invented, so the climbing can come out a little lower than the original’s.

Questions

What tolerance should I use?

Start at 5 m: on a walk or a ride it removes most of the points and the line still sits on the path. Raise it until the count is under your device’s limit, and check the map.

How many points does my device take?

It varies by model and by whether it is a route or a track; some older units take a few hundred points per route, newer ones many thousands. The live count tells you when you are under the number your manual gives.

Will the distance change?

A little: cutting corners off a wiggly line makes it slightly shorter. The new distance shows beside the count so you can see by how much.

Are stops removed?

Points under a metre from the one before, where the watch stood still, go at any tolerance. The times of the points that stay are kept, so a long stop still shows in the clock.