CRG File

What are CRG files and how to open them

Are you having problems opening a CRG 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 CRG files.

What is a CRG file?

A .CRG file is a Calamus Raster Graphic Bitmap file.

Calamus Raster Graphic Bitmap is a monochrome image format used by the desktop-publishing program Calamus (originally on Atari ST systems) to store bitmapped graphics for layout work. These files represent black-and-white (single-bit) images, often textured line art or scanned halftone images, for use in document layouts and printing.

Files in this format are produced by Calamus when exporting raster graphic content, or internally when Calamus stores monochrome graphics for use in picture or raster graphics frames. After creation they may be imported into Calamus documents or previewed within the program. They serve in workflows that require sharp contrast images without grayscale shades, suitable for line art reproduction or high-contrast printing.

A specific identifying feature of files of this format is a 8-character ASCII signature at the beginning: CALAMUSCRG starting at byte offset zero.

How to open CRG files

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

While we have not verified the apps ourselves yet, our users have suggested five different CRG openers which you will find listed below.

Last updated: September 18, 2026

Various apps that use files with this extension

These apps are known to open certain types of CRG files. Remember, different programs may use CRG 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 CRG file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.