.QGS File Extension

A QGS file is a project created by QGIS, an open-source cross-platform GIS application. It contains the state of a workspace in QGIS, which includes layer properties, references to GIS data, default project styles, the layer tree, and the project title. QGS files are saved in XML format.

QGIS is used by various amateur and professional users to create, edit, visualize, and publish geospatial information. When a user saves a project by selecting Project → Save or Project → Save As..., QGIS creates a QGS file to store the information.

As the user saves a project with QGIS, the program creates a backup file in the same directory as the QGS project file. The backup file has the .qgs~ file extension.

You can open a QGS file with QGIS by selecting Project → Open....

Since QGS files are saved in XML format, you can also open a QGS file with an XML or text editor to view the contents. Keep in mind that the contents will not appear the same as if they were being viewed with QGIS.