GML Viewer Online
Upload and visualize GML files on an interactive map
🔒 All processing happens locally in your browser. Your files never leave your device.
About GML files
GML (Geography Markup Language) is the OGC's XML grammar for geographic features. Most people meet it not by choosing it but by being handed it: it is the default response format of many WFS services, the mandated delivery format for EU INSPIRE datasets, and a common export from European cadastral and planning authorities.
That makes GML awkward to open casually. It is verbose XML, the feature types are defined by a schema rather than fixed by the format, and a single file can nest several namespaces. Desktop GIS handles it, but installing QGIS to check whether a download actually contains what you expected is a lot of ceremony. This viewer reads the file with GDAL in your browser and draws the geometry on a map, so you can confirm the contents in a few seconds.
Common questions
What is a GML file?
GML (Geography Markup Language) is an OGC standard XML format for describing geographic features — their geometry, attributes, and relationships. It is widely used by WFS web services, EU INSPIRE data deliveries, and European government open-data portals. The .gml extension is most common, though the same content sometimes arrives as .xml.
Do I need the .xsd schema file to open a GML file?
Not for viewing. When an application schema (.xsd) is not present, GDAL scans the document and infers the feature types and attribute types from the data itself. That is enough to render the geometry and read the attributes. A schema mainly helps by pinning down exact data types, so a field that looks numeric is not guessed as text.
Why do my GML coordinates appear in the wrong place?
Almost always axis order. GML files declare their CRS in an srsName attribute, and for EPSG-coded geographic systems the authority definition puts latitude first, while GeoJSON and most web maps expect longitude first. A file written by a strict OGC service can therefore appear transposed — points landing in the wrong hemisphere is the classic symptom. If your features render somewhere unexpected, check the srsName and the axis order it implies before assuming the data is wrong.
Is my GML file uploaded to a server?
No. The file is read and rendered entirely inside your browser tab using a WebAssembly build of GDAL. Nothing is transmitted, which means you can inspect confidential or licence-restricted deliveries without them leaving your device.
GML data downloaded from WFS services or national spatial data infrastructures is verbose XML that is difficult to read directly — viewing it here renders the features on a map so you can quickly assess geometry and attributes.