KML Viewer

Open a KML file from Google Earth, My Maps, or any GIS export and see what is inside it: every placemark drawn on a lightweight map, and a list of names with their descriptions. Points, paths, and polygons are all rendered, fitted to the data so the shapes fill the frame. The map is built locally from the coordinates with no basemap tiles, so the file is parsed entirely in your browser and nothing is uploaded — saved locations and boundaries stay on your machine.

How to use the KML Viewer

Paste KML text into the box or load a .kml file. KML files exported from Google Earth or Google My Maps are often saved as .kmz, which is a zipped KML — unzip it first and open the doc.kml inside, since this viewer reads the uncompressed XML. The parser is namespace-agnostic, so files that declare the OGC KML namespace and files that omit it both work.

Once parsed, every <Placemark> is read for its geometry. A <Point> becomes a dot, a <LineString> becomes a path, and a <Polygon> becomes a filled outline, with inner boundary rings drawn as holes. All of it is fitted to the combined bounding box and drawn onto a compact map. Below the map, each placemark is listed with its name, the geometry types it contains, and the first part of its description, so you can match a shape on the map to its label.

The status line reports how many placemarks were found, a breakdown of point, line, and polygon geometries, and the total coordinate count, along with the longitude and latitude bounds. KML writes coordinates as longitude,latitude,elevation tuples separated by spaces, which is the reverse of how the comma-separated pair usually reads aloud, so if a shape lands in the wrong place the coordinate order in the source is the first thing to check. If the text is not well-formed XML, or its root element is not <kml>, the viewer reports that rather than drawing nothing.

What KML is and where it comes from

KML, the Keyhole Markup Language, is an XML format for describing geographic features: points, lines, polygons, images, and the styling that goes with them. It was created by Keyhole, the company whose Earth-browsing software Google acquired and turned into Google Earth, and the name stuck. In 2008 KML became an open standard of the Open Geospatial Consortium, so although it is forever associated with Google Earth, it is a vendor-neutral specification that many GIS tools read and write.

The building block is the Placemark, which pairs a geometry with a name and an optional description. The geometry is one of a small set of types: a Point for a single location, a LineString for a path, a Polygon for an area with an outer boundary and optional inner holes, and a MultiGeometry for grouping several together. Placemarks are organised into Folder and Document containers, which is how a single KML file can hold a whole annotated map with dozens of layers. Coordinates are written as longitude,latitude,altitude tuples, comma-separated within a tuple and whitespace-separated between tuples, all in WGS 84.

What sets KML apart from a plain geometry format is how much presentation it carries. A KML file can specify icon images for points, line colours and widths, polygon fills, balloon HTML that pops up when a feature is clicked, and even camera positions and time spans for animated tours. That richness is why it became the format for sharing annotated maps: a recipient opening the file in Google Earth sees not just the shapes but the intended styling and labels. The trade-off is that KML files are verbose and their styling is tied to Earth-style viewers, which is why data-exchange pipelines often convert KML to the leaner GeoJSON. When you just need to see what locations and boundaries a KML actually contains, drawing the geometry and listing the placemark names is the fastest way to understand it.

Common use cases

• Inspecting a My Maps export. See the points and routes inside a KML before importing it into another tool.
• Auditing shared boundaries. Confirm that the polygons in a delivered KML cover the areas you expect.
• Reading placemark names. List every named location in a file without opening Google Earth.
• Debugging a conversion. Check coordinate order and geometry types before converting KML to GeoJSON or a shapefile.