map
shaper
Settings
Console
Basemap
Simplify
Export
Wiki
GitHub
Unfortunately, mapshaper can't run in
this web browser
For best results, try
Google Chrome
or
Mozilla Firefox
.
Layers
No data has been added
Source files
Add files
Add empty layer
Select
Clip
Erase
Rectangle
Frame
Bounds
Cancel
Delete
Keep
Duplicate
Split
Bounds
Edit data
Clear
Export options
Layers
File format
?
Enter options from the command line interface for the -o command. Examples: bbox no-quantization precision=0.001. Click to see all options.
choose output directory
save to clipboard
Export
Basemap options
Map
Satellite
Clear
Fade
Simplification
prevent shape removal
?
Prevent small polygon features from disappearing at high simplification. Keeps the largest ring of multi-ring features.
use planar geometry
?
Treat x, y values as Cartesian coordinates on a plane, rather than as longitude, latitude coordinates on a sphere.
Method
Douglas-Peucker
?
Simplified lines remain within a set distance of original lines. Good for thinning dense points, but spikes tend to form at high simplification.
Visvalingam / effective area
?
Lines are simplified by iteratively removing the point that forms the least-area triangle with two adjacent points.
Visvalingam / weighted area
?
Points located at the vertex of more acute angles are preferentially removed, for a smoother appearance.
Apply
Import files
with advanced options
Drop, paste or
select
files to import.
Shapefile, GeoJSON, TopoJSON, KML and CSV formats are supported. Files can be zipped or gzipped.
?
Enter options from the command line interface. Examples:
snap no-topology encoding=big5
. Click to see all options.
Submit
Enter mapshaper commands or type "tips" for examples and console help
$
Check line intersections
0 line intersections
Repair
◀
▶