CAG File

What are CAG files and how to open them

Are you having problems opening a CAG file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your CAG files.

What is a CAG file?

CAG files have multiple uses, and Capella Gallery Data is one of them. Read more about the other uses further down the page.

Capella Gallery Data File

These CAG files contain the music sheets created in Capella's Tonica Fugata, a music sheet editor. You could create your own compositions with the help of a program that tells you if you added the right notes to the correct chords.

How to open CAG files

Important: Different programs may use files with the CAG file extension for different purposes, so unless you are sure which format your CAG file is, you may need to try a few different programs.

While we have not verified the app ourselves yet, our users have suggested a single CAG opener which you will find listed below.

Last updated: August 25, 2026

All known file formats using extension .CAG

While Capella Gallery Data File is a popular type of CAG-file, we know of 3 different uses of the .CAG file extension. Different software may use files with the same extension for different types of data.

Create Adventure Games Project

These CAG files contain the games created in CAG (Create Adventure Games), a program developed by Marco Pinto and is used to create adventure games. This program was used on the Amiga, a personal home computer that was popular in the 1980s and 1990s.

Microsoft Clip Art Gallery Catalog

Microsoft Clip Art Gallery Catalog files are a database format used by Microsoft Clip Gallery (versions 2.0 and 3.0, among others) to store metadata and preview images for clip art collections. They contain organizational information - such as categories and descriptions - and small thumbnail images, plus references to the full clip art graphics. These catalog files make it possible for the Clip Gallery program and compatible Office applications to browse clip art by category instead of showing every clip as a flat list.

Creation of these catalog files is done by Microsoft Clip Gallery or programs in the Office suite that include Clip Gallery functionality. When clip art or new collections are added (via Clip Gallery's "Import Clips" or "Add Pictures" commands), this catalog file is updated to include new entries or thumbnail previews. It serves as an index, helping the Clip Gallery display clip art when a user searches or browses by category.

On the technical side, these catalog files start with a compound file header (bytes D0 CF 11 E0 A1 B1 1A E1 at offset zero) consistent with Microsoft's Structured Storage format. Later in the file are searchable Unicode strings such as "CATEGORY" and "THUMB", plus markers like "(ALL CATEGORIES)", "RECT", "UNIT", and "COUNT" that identify sections of metadata, category listing, thumbnail definitions and layout information.

Various apps that use files with this extension

These apps are known to open certain types of CAG files. Remember, different programs may use CAG files for different purposes, so you may need to try out a few of them to be able to open your specific file.

Help us help others

File.org helps thousands of users every day, and we would love to hear from you if you have additional information about CAG file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.