Free online JPG to KMZ converter

Google Earth and GIS applications use KMZ when an image must be shared with its geographic placement and display instructions in one file. Converting an ordinary JPG requires defining its position first; a file containing only pixels cannot provide a reliable map location.

What the JPG format is

JPG, also called JPEG, is a lossy raster format used for photographs, scans, screenshots, aerial imagery, and exported maps. Cameras, phones, scanners, web browsers, Adobe Photoshop, GIMP, and office applications commonly create or open it. A JPG stores pixels but normally has no boundary coordinates or coordinate reference system.

Some cameras and phones write GPS coordinates to JPG EXIF metadata. Those coordinates usually identify the camera position, not the image footprint, corners, orientation, or scale, so EXIF geotags alone do not accurately georeference a scanned map or aerial image. A companion world file such as .jgw, usually with a matching .prj, can supply raster placement information.

What the KMZ format is

KMZ is a ZIP-compressed package that normally contains a KML document and associated resources such as JPG or PNG images. KML describes geographic objects, including placemarks, paths, polygons, image overlays, and camera views. A JPG is commonly packaged as a KML GroundOverlay, whose coordinates define where the image appears on the earth.

Google Earth Pro, Google Earth Web, QGIS, ArcGIS, and other geospatial applications can import KMZ. Packaging the KML and image together avoids broken external image links during sharing or archiving. KMZ is a container, not a georeferencing method; the KML must contain valid placement data.

How to convert a JPG to KMZ

For approximate placement in Google Earth Pro

1. Open Google Earth Pro on Windows, macOS, or Linux.
2. Choose Add → Image Overlay, enter a name, and use Browse to select the JPG.
3. Move, resize, and rotate the overlay over identifiable map features. Enter known coordinates or use surveyed control points when accuracy matters; visual alignment alone is approximate.
4. Adjust transparency to compare the image with the basemap, then click OK.
5. In the Places panel, right-click the overlay and choose Save Place As. Select KMZ and save the file.

This method creates a KML overlay with the JPG embedded or referenced inside the KMZ. It is appropriate for a quick map overlay, not for survey-grade registration.

For measured georeferencing in QGIS

1. Open QGIS and choose Raster → Georeferencer → Georeferencer.
2. Load the JPG and add at least three known control points whose coordinates are available from a reference layer, map grid, or survey. Distribute additional points across the image to expose distortion.
3. Set the correct target CRS and transformation, then run the process to create a georeferenced GeoTIFF or another georeferenced raster.
4. Use the resulting raster with GDAL to create a KMZ super-overlay, or use a QGIS workflow that exports a raster overlay to KML/KMZ. Confirm that the output uses WGS 84 geographic coordinates, as required by KML.

QGIS is the better choice for scanned maps, aerial images, and other sources that need control points or a defined CRS. If the JPG already has a valid .jgw and .prj, load it with those companion files and verify its placement before exporting.

For repeatable processing with GDAL

After the raster has valid georeferencing, GDAL can create a tiled KML super-overlay:

gdal_translate -of KMLSUPEROVERLAY input.tif output.kmz

GDAL transforms supported source CRS data to the coordinate system used by KML and creates tiles for large images. A plain JPG without georeferencing, a world file, or other spatial metadata cannot be correctly positioned by this command alone. Test the command with the GDAL version installed on the system because available drivers and output behavior vary by build.

Using an online converter

MyGeodata Cloud and similar GIS conversion services can convert georeferenced raster data to KMZ. Uploading an ordinary JPG does not let the service determine its real-world location; provide spatial metadata or use the service's control-point or overlay tools if available. Check the accepted CRS, maximum file size, output type, and data-retention policy before uploading. Use Google Earth Pro, QGIS, or GDAL locally for confidential imagery, field photographs, or large rasters, then open the downloaded KMZ to verify its position and image links.

Quality and compatibility limits

Conversion does not restore detail lost through JPEG compression. Avoid opening and re-saving the source as JPG before packaging it, because another lossy-compression cycle can reduce quality. PNG is usually better for line drawings, labels, and transparency, although the KML may still reference a JPG when its smaller size is useful.

Large single-image overlays can load slowly in Google Earth and other clients. A KML super-overlay with multiple resolution tiles is more suitable for large aerial or scanned imagery. Keep all referenced resources inside the KMZ and preserve relative paths; manually renaming or deleting files in the ZIP archive can make the overlay fail. Verify the CRS, image extent, antimeridian behavior, transparency, and alignment in the target application because KMZ support and rendering details differ between programs.