KMZ to KML and back: converting online and by hand

You need to turn a .kmz into a .kml (or the other way round), and there's no special program at hand. Good news: this is one of the simplest conversions, because KMZ and KML are almost the same thing. Let's cover both the manual way and how to get a ready file straight away.

KMZ and KML — what's the difference

KMZ is a ZIP archive with KML inside. KML (Keyhole Markup Language) is Google's text-based XML format for geographic data: points, lines, polygons, placemarks. To make the file smaller and let it carry attachments (icons, images), it's packed into a ZIP and given the .kmz extension. So KMZ is simply "compressed KML".

From this follows the main point: converting KMZ ↔ KML is unpacking or packing a ZIP, not recomputing the data. The geometry and coordinates don't change.

KMZ → KML by hand (in a minute)

1. Copy the file and change the extension: map.kmz → map.zip.
2. Unpack it with any archiver (7-Zip, WinRAR, the one built into Windows/macOS).
3. Inside you'll find a doc.kml file (sometimes with a different name) plus, possibly, a folder of icons. That is your KML.

The doc.kml file is plain text — you can open it even in Notepad. If Windows doesn't show extensions, enable them: Explorer → View → "File name extensions".

KML → KMZ by hand

The reverse is just packing:

1. Put doc.kml (and the icons folder, if any) into a ZIP archive.
2. Change the archive extension from .zip to .kmz.

Done — you've got a KMZ. It's more compact and handier for carrying to a device or into Google Earth with pictures.

The online way

If you'd rather not fiddle with an archiver, KMZ and KML are opened and re-saved by programs that work online or locally:

• Google Earth (web or Pro) — opens both KMZ and KML and can save "as KML" or "as KMZ".
• QGIS — opens both formats (Layer → Add Vector Layer) and exports to either via Export → Save Features As.

More on opening KMZ in different ways is in How to open KMZ. A technical breakdown of the format is in KMZ: a deep dive.

Easier — get a ready file straight away

Often people convert KMZ/KML not for the format's sake but because they need a map of an area. Then don't wrestle with someone else's file:

• if you already have a file and need to turn it into KML — use our KMZ → KML converter;
• if you need a map of a territory — select the area and download it straight as KML or KMZ; for web and GIS, GeoJSON is handier.

You get a clean map of the right territory with OpenStreetMap layers, instead of figuring out someone else's archive. It's free and takes seconds.

In short

• KMZ = a ZIP with KML inside; converting ↔ = unpacking/packing, the data doesn't change.
• KMZ → KML: rename to .zip, unpack, take doc.kml.
• KML → KMZ: pack into a ZIP, change the extension to .kmz.
• Online — Google Earth or QGIS; a ready file — the KMZ → KML converter or download an area as KML/KMZ.