Keyhole Markup Language (zipped) .kmz
Google Earth packages with COLLADA geometry inside.
What a .kmz file holds
A KMZ is a zip archive holding a KML document plus the assets it references, and when that KML places a 3D model, the geometry inside is COLLADA. It is how buildings and terrain models were distributed for Google Earth and SketchUp’s 3D Warehouse, so a lot of architectural and city-scale geometry is sitting in .kmz files.
Commonly seen in: Google Earth, SketchUp, 3D Warehouse archives, GIS tooling.
| Data | Stored in KMZ |
|---|---|
| Geometry | Yes |
| Materials and colour | Yes |
| Texture maps | Yes |
| Animation and rigs | No |
| Scene hierarchy | Yes |
| Read here | Yes |
| Written here | No |
Tested against a real file
The last sweep loaded Box.kmz from three.js examples through the viewer on this site: 12 triangles across 1 meshes and 1 materials, in 1.9 seconds. Every format's result is on the test results page, run 2026-09-08.
Convert KMZ to another format
Every pairing has a page saying what survives the trip.
Other things to do with a .kmz file
Questions about KMZ
How do I open a .kmz file?
Drop it into the viewer on this site and it opens in the browser, with the scene tree, the materials and the mesh statistics. Nothing is uploaded. If you want it in another program instead, convert it to GLB, which almost everything reads.
Is KMZ a good format to archive in?
KMZ stores geometry, materials and colour, texture maps, scene hierarchy. Anything outside that list will not be in the file at all, so archive the original alongside it if the surfacing or the rig matters.
Does converting KMZ lose quality?
Geometry is copied vertex for vertex, so the shape does not degrade. What gets lost is whatever the target format has no field for: convert to STL and the materials go, convert to OBJ and the animation goes. The comparison table on each converter page says exactly which.
Formats that hold the same things
Or go back to the full format reference.