Free · Turn an outline into an area

GeoJSON Line to Polygon Converter

Close a GeoJSON line and turn it into a polygon feature.

  • Clear map preview
  • Private in your browser
  • GeoJSON download

Work with map data

Use the example or add your own GeoJSON. Results stay in this browser tab.

Result view
Making the map resultTurf is loading in this tab.
StatusLoading
EngineTurf.js
PrivacyLocal
FormatGeoJSON

Three simple steps

How to use it

  1. Paste a LineString or MultiLineString.
  2. Check that the new closing edge makes the area you expect.
  3. Check the map, then copy or download the GeoJSON result.

Your map data stays on this device

Turf.js reads and changes the GeoJSON inside this browser tab. Bookify does not upload or save it. Close the tab and the working copy is gone.