KML — Keyhole Markup Language — has been around since 2004 and remains one of the most widely shared geographic data formats in the world. Engineers share KML files of survey routes. Planners distribute KML files of proposed development boundaries. Field teams send KML files of asset locations. Despite being two decades old, KML is not going anywhere, which means GIS professionals need to know how to work with it efficiently — often without Google Earth.

What Is KML and What Is KMZ?

KML (Keyhole Markup Language) is an XML-based format for storing geographic features — placemarks, paths, polygons, and overlays — along with their styling and descriptive information. KMZ is simply a compressed (zipped) version of a KML file, often used when the KML includes embedded images or large datasets.

KML was developed by Keyhole Inc. (acquired by Google in 2004), standardised by the Open Geospatial Consortium in 2008, and became the native format of Google Earth. Today it is supported by Google Maps, ArcGIS, QGIS, and virtually every web mapping library.

Why You Might Need to Work with KML Outside of Google Earth

Google Earth is the obvious tool for KML files, but there are several scenarios where it is not the right choice:

• You need to share a preview with a colleague who does not have Google Earth installed.
• You need to import KML data into a CAD system like AutoCAD, which requires DXF format.
• You need to extract the attribute table from a KML file into Excel for analysis.
• You need to convert KML to GeoJSON for use in a web mapping application.
• You need to produce a PDF map of the KML data for a report or client deliverable.

All of these tasks are possible directly in the browser, with no software installation required.

How to View KML Files Online

The Quick Map Tools KML viewer supports both .kml and .kmz files. Drag your file onto the viewer, and your placemarks, paths, and polygons appear on an interactive map. No Google Earth installation, no Google account, no file size restrictions that force you to split your data. Click any feature to see its name, description, and other attributes.

This is useful for a quick visual check before sending a file to a client, validating that a field team’s survey data covered the expected area, or simply confirming that coordinates are in the right location before importing into a larger workflow.

Converting KML to Other Formats

KML to PDF

The most commonly requested KML conversion. Engineers, planners, and project managers frequently need a static PDF map of KML data for reports, presentations, and regulatory submissions. The KML to PDF converter on Quick Map Tools handles this in seconds — upload your KML or KMZ file and download a printable PDF map. This is the highest-traffic tool on the Quick Map Tools site because the need is so universal and the alternatives (exporting from Google Earth, screenshotting, using desktop GIS) are all significantly more cumbersome.

KML to GeoJSON

For web mapping applications, GeoJSON is almost always the preferred format. If you have received KML data and need to load it into a Leaflet, MapLibre, or Mapbox application, converting KML to GeoJSON is the first step. The conversion preserves all geometry and attribute data. For the reverse operation — converting GeoJSON back to KML — see our guide on viewing and working with GeoJSON files.

KML to DXF (AutoCAD)

Surveyors and civil engineers regularly need to import geographic data into CAD software. DXF is the exchange format that AutoCAD, MicroStation, and similar tools accept. The KML to DXF converter exports your KML geometry into a DXF file ready for CAD import, preserving line work and polygon boundaries. Note that KML styling (colours, labels) does not translate directly into DXF — the geometry transfers cleanly, but you will need to apply CAD layers and styling after import.

KML to Excel (XLSX)

KML placemarks contain attribute data — names, descriptions, and custom fields — that is often more useful in a spreadsheet than in a map. The KML to Excel converter extracts this data along with the coordinates of each feature into an XLSX file. This is particularly useful for asset registers, site lists, and any dataset where the tabular data matters as much as the geometry.

Working with GPX Data Alongside KML

KML and GPX often appear together in fieldwork contexts. KML defines the planned survey area or asset locations; GPX captures the actual GPS tracks recorded in the field. If you are working with both formats, our guide on working with GPX files in GIS covers viewing and converting GPS track data in the browser.

KML Limitations to Be Aware Of

KML is excellent for its intended purpose — data interchange with Google Earth — but has limitations worth understanding before choosing it as your primary format:

• No native coordinate system support: KML always uses WGS84 geographic coordinates. If your workflow uses projected coordinates, you need to convert before creating KML.
• Limited attribute typing: KML attributes are stored as strings. Numeric data, dates, and booleans are all represented as plain text, which can cause issues when importing into databases or analysis tools.
• Styling is Google-specific: KML’s styling markup (icons, line colours, fill opacity) is interpreted by Google Earth but is largely ignored by other tools.
• Large files become slow: KML with tens of thousands of features starts to degrade in Google Earth. For large datasets, GeoJSON, GeoPackage, or a vector tile format is a better choice.

Summary

KML remains a practical and widely-used format for geographic data exchange, particularly in workflows that touch Google Earth, Google Maps, or non-GIS tools like Excel. Browser-based tools remove the friction of dealing with KML: the KML viewer handles quick inspection, and the converters for PDF, GeoJSON, DXF, and Excel cover the most common downstream tasks without requiring any software installation.