CSL File

What are CSL files and how to open them

Are you having problems opening a CSL 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 CSL files.

What is a CSL file?

CSL files have multiple uses, and Calamus Style List is one of them. Read more about the other uses further down the page.

Calamus Style List

These CSL files contain the list of different text styles used in Calamus, a desktop publishing application built for Atari ST, a personal home computer released in 1985. These text styles are used in your documents/pages that you created in Calamus.

How to open CSL files

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

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

Last updated: September 19, 2026

All known file formats using extension .CSL

While Calamus Style List is a popular type of CSL-file, we know of 3 different uses of the .CSL file extension. Different software may use files with the same extension for different types of data.

Citation Style Language

CSL files provide access to thousands of citation-styles and make formatting citations much easier. They are important for automating scholarly communication and helping researchers stay organized. CSL files are compatible with many tools such as BibGuru, Auratikum, and MindView.

Corel Symbol Library

Corel Symbol Library files store reusable graphic symbols defined in CorelDRAW. They are created when a user saves or exports symbols from a drawing into a library. These library files let designers build a collection of frequently used graphics - such as logos, shapes, or icons - and reuse them across multiple documents without recreating each element. Symbols inside the library are defined once, and when used in a drawing, they appear as instances that refer back to the single definition, keeping file size down and edit workflows efficient.

The CorelDRAW application is responsible for both creating and reading these symbol library files. In CorelDRAW or Corel DESIGNER, users create symbols from objects in drawings, then either save the entire document as a symbol library file so that all symbols plus their instances are included, or export just the symbol definitions. Once saved, a library file can be stored locally, placed on a network, or uploaded to Corel's cloud. Other drawings can link to external libraries (.csl files), allowing symbols to update automatically when the library changes.

Files begin with a RIFF-based structure: the header starts with ASCII "RIFF" at offset 0, followed at offset 8 by "CSL", and include chunks such as "vrsn", "DISP", "LIST4'''CMPR", among others. The version identifier appears at a fixed position in the structure (e.g., character at position 11). Other internal tags include "INFOIKEY", "CPNG", "ICMT", and "SUMI".

Various apps that use files with this extension

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