How KMZ works
Structurally a KMZ is just a compressed container: unzip it and you get a main doc.kml plus an optional folder of supporting files. Zipping typically shrinks verbose KML text substantially and keeps a placemark set and its custom icons together as one shareable file, which is why Google Earth exports KMZ by default. Everything true of KML applies to the KML inside a KMZ; the wrapper only adds compression and asset bundling.
Coordinate systems and reprojection
Because the payload is ordinary KML, a KMZ is inherently WGS84 (EPSG:4326) longitude/latitude/altitude, with no projection metadata and no possibility of reprojection inside the format.
Compare KMZ with other GIS formats
Convert KMZ to another format
Choose a conversion below for the online converter, format-specific caveats, and step-by-step instructions for KMZ.
Convert files to KMZ
Frequently asked questions
- What file extension does KMZ use?
- KMZ uses .kmz (a zipped doc.kml).
- Does KMZ store a coordinate system?
- Because the payload is ordinary KML, a KMZ is inherently WGS84 (EPSG:4326) longitude/latitude/altitude, with no projection metadata and no possibility of reprojection inside the format.
- Can I convert KMZ online?
- Yes. GeoConvert can read or write KMZ in your browser for the conversion paths listed above, without uploading free-tier files to a server.