KMZ
A zipped KML bundle — bring your icons and overlays along for the ride.
- Specification
- OGC KML 2.3 (packaging)
- Released
- 2004
- When to use
- Use KMZ when you want to deliver a single file to a recipient who will open it in Google Earth and you need to include custom icons, photo overlays, or 3D models alongside the KML. For pure geometry exchange, plain KML or GeoJSON is simpler. For programmatic processing, always extract the inner doc.kml first.
What is KMZ?
A KMZ file is nothing more than a ZIP archive whose primary entry is a KML document (conventionally named doc.kml) at the archive root, optionally accompanied by image files, icon PNGs, COLLADA (.dae) 3D models, and other resources that the KML references with relative paths. The KMZ packaging exists because a useful Google Earth tour usually depends on multiple files: a screen overlay logo, a folder of placemark icons, photo overlays positioned over the ground, and the central KML that wires them together. Zipping the bundle solves the distribution problem (one file to email, upload, or share) and compression cuts the typical 5–10× XML overhead of KML. Google Earth treats .kml and .kmz interchangeably. Most other tools — including this site's KML validator and converters — require the user to extract the .kml from the archive first, because the inner KML is what carries the geometry.
Supported by
- Google Earth (desktop, web, mobile) — native
- Google My Maps (import/export)
- QGIS (via GDAL LIBKML)
- ArcGIS Pro
- GDAL/OGR (drivers: KMZ via LIBKML)
- FME, Global Mapper
- Most photo-mapping and drone-survey tools
Strengths
- Single-file delivery — emails, USB sticks, downloads in one click
- Bundles icons, overlays, and 3D models with the KML in one package
- Compression typically cuts KML size by 80% or more
- Same renderer behaviour as KML in Google Earth
Weaknesses
- Most non-Google-Earth tools require manual extraction
- Validators usually reject KMZ directly — they need the inner KML
- Updating one icon means rebuilding the archive
- Filename of the inner KML is convention, not enforced — some readers only look for doc.kml
Frequently Asked Questions
How do I extract the KML from a KMZ?
A .kmz is a standard ZIP file with a renamed extension. Rename it to .zip, double-click to extract, and you'll find doc.kml (or a similarly named .kml) inside. On macOS/Linux: unzip file.kmz -d extracted/. On Windows: right-click → Open with → File Explorer.
Can I upload a KMZ directly to your converter or validator?
Not yet. Our online tools accept plain .kml at the moment. Extract the inner .kml from your .kmz archive and upload that instead. If you need command-line conversion, ogr2ogr handles KMZ directly when GDAL is built with LIBKML.
What's inside the typical KMZ?
At minimum: a doc.kml at the archive root. Often also: a /files or /icons folder with PNG markers, JPEG photo overlays positioned with <PhotoOverlay>, and occasionally COLLADA .dae files for 3D buildings. All resource references inside the KML are relative paths into the archive.
Does KMZ compress better than ZIPping a KML manually?
No — KMZ uses standard ZIP deflate compression, so the ratio is identical. The difference is convention: the .kmz extension tells Google Earth to open the archive directly without prompting.