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Edit a file

Drag and drop or select a file to import. Shapefile, GeoJSON and TopoJSON files and Zip archives are supported.

Simplification method

Points located at the vertex of more acute angles are preferentially removed, for a smoother appearance.
Lines are simplified by iteratively removing the point that forms the least-area triangle with two adjacent points.
Simplified lines remain within a given distance of original lines. Good for thinning dense points but tends to form spikes at high simplification.

Other options

Remove line intersections. Works by rolling back simplification along intersecting segments.
Automatically fix minor topology errors by snapping together points that are almost identical. Doesn't apply to TopoJSON files.
Prevent small polygons from disappearing at high simplification. Protects the largest ring of multi- ring features.
coordinate precision
Round coordinates by a specified precision. Reduces the size of GeoJSON files but can cause intersections and collapsed shapes. Uses same units as the source file, e.g. decimal degrees for most unprojected files.
0 line intersections