Free online KMZ to GLTF converter

Google Earth and GIS packages commonly deliver 3D content as KMZ, while web viewers, game engines, and AR tools often require glTF or GLB. Converting the package makes its local model usable in those applications, but geographic placement and KML-only content may need separate handling.

What KMZ contains

KMZ is a ZIP-compressed package containing KML (Keyhole Markup Language) data. Google Earth, Google Earth Pro, SketchUp exports, and GIS or mapping applications use it for placemarks, paths, polygons, camera views, geographic coordinates, and 3D models.

A KMZ commonly contains doc.kml, one or more COLLADA .dae files, and image textures such as .jpg or .png. It is not necessarily a 3D mesh: some packages contain only map features, labels, terrain references, overlays, or links to remote data. Conversion produces a model only when local 3D geometry is present or the referenced geometry can be obtained.

What glTF provides

glTF is an open runtime 3D format maintained by the Khronos Group. It represents scene nodes, meshes, materials, textures, cameras, and animations for efficient loading in browsers, real-time viewers, game engines, and AR applications.

A .gltf asset normally uses a JSON scene file plus separate binary and image files. A .glb file is the binary form and can package the scene, mesh data, and textures in one file, making it the usual choice for sharing. glTF materials are primarily physically based and do not preserve every COLLADA or Blender material feature.

Extract the KMZ package

1. Keep an untouched copy of the original .kmz file.
2. Open the file with a ZIP-compatible archive utility, or rename model.kmz to model.zip and extract it.
3. Extract the complete folder structure, including doc.kml, .dae files, and image textures. Relative paths in the KML and COLLADA files depend on those folders remaining together.
4. Open doc.kml in a text editor and inspect its <Model> and <Link> elements to identify the referenced COLLADA file. If there is no local .dae file, the package may not contain convertible 3D geometry.

Convert the model with Blender

1. Install a current Blender release with its COLLADA importer and glTF exporter available.
2. Choose File → Import → Collada (.dae), then select the extracted .dae file from its original folder. Do not move the file away from its textures before importing.
3. Inspect the result in Material Preview or Rendered view. If images are missing, use File → External Data → Find Missing Files and select the extracted resource directory.
4. Check scale, normals, hierarchy, duplicate objects, and polygon count. Remove cameras, lights, or empty nodes that are not needed. Apply transforms with Object → Apply → All Transforms only after confirming the desired orientation and scale.
5. Choose File → Export → glTF 2.0. Set the format to glTF Binary (.glb) for one portable file, or to glTF Separate (.gltf + .bin + textures) when the destination requires separate assets.
6. Enable Selected Objects when only the imported model should be exported. Use image textures and standard physically based material inputs; procedural Blender nodes and unsupported shader features may be simplified or omitted.
7. Open the exported file in the target viewer or engine and check geometry, textures, orientation, scale, and animation before delivery.

Users who do not need local editing can upload the KMZ to 101convert.com for free conversion without installing software. Automatic conversion is less suitable when the package has missing network resources, unusual COLLADA features, multiple models, or KML placement that must be preserved precisely.

Quality and compatibility limits

KML can place a model with latitude, longitude, altitude, heading, tilt, and roll. glTF normally stores a local scene coordinate system, so the original map position is not automatically equivalent in the exported asset. Record the KML coordinates separately, or apply a local origin and retain the geographic metadata for use in a GIS or geospatial engine.

Very large geographic coordinates can cause floating-point precision problems in real-time applications. Recenter the mesh near the origin before export when appropriate, while preserving the original geographic position outside the glTF file.

Textures referenced by remote URLs, Google Earth-specific paths, or incorrect case-sensitive filenames may not load. Download resources where permitted, convert unsupported image formats to PNG or JPEG, and verify every texture path before export.

COLLADA imports may have reversed normals, incorrect units, duplicated materials, missing animations, or excessive geometry. Inspect and correct these issues in Blender. The conversion generally does not preserve KML labels, map overlays, network links, terrain behavior, or Google Earth presentation settings; it exports the available 3D scene rather than the complete map visualization.