KML viewer

What is read from each placemark

For every Placemark the viewer keeps the name and description, then reads each Point, LineString, and Polygon inside it. Polygons keep their outer boundary and any holes. A placemark with several shapes becomes several features with the same name.

How to use it

1. Drop your .kml file onto the box, or click to choose it. Unzip .kmz files first.
2. Points, lines, and polygons appear on the map, which zooms to fit them.
3. The line beside the export buttons gives the number of features and, if there are lines, their total length.
4. Press GeoJSON or GPX to convert. The KML button writes a clean copy of the parsed data.

About KML

KML is an XML format for geographic data, first built for Google Earth and now an OGC standard. Coordinates in KML are written as longitude, latitude, and optional altitude, separated by commas, with spaces between points.

Styles, icons, network links, and 3D models are not drawn. The viewer is for checking and converting geometry, not for reproducing Google Earth's look.

KMZ files

A .kmz file is a zipped KML. Rename it to .zip, extract it, and open the doc.kml inside. The viewer does not unzip files itself.

Converting to GeoJSON or GPX

GeoJSON export keeps points, lines, and polygons with their names and descriptions. It is the format most web maps and GIS tools prefer. GPX export keeps points as waypoints and lines as tracks, which is what GPS devices and hiking apps expect. GPX has no polygon type, so polygons are written as closed tracks.

To open the result again, use the GeoJSON viewer or the GPX viewer.

Getting a KML file

In Google Earth, right-click a folder or placemark and save it as a .kml file. In Google My Maps, use the export option and tick the box for KML instead of KMZ. Many GPS apps and government data portals also offer KML downloads.

Large files with thousands of placemarks can take a few seconds to draw. The 8 MB limit covers most exports. If a file shows nothing, open it in a text editor and check that it contains Placemark elements with coordinates, since some KML files only link to data stored elsewhere through network links. Those links are not followed.