CLS File Type

- The quick facts

What are CLS files and how to open them

Are you having problems opening a CLS file or just wondering what they contain? We explain what these files are used for and show you software that we know can open or otherwise handle your files.

What is a CLS file?

A .CLS file is a Visual Basic Class Definition file.

We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

How to open CLS files

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

While we have not verified the apps ourselves yet, our users have suggested 10 different CLS openers which you will find listed below.

Last updated: May 31, 2022

Various apps that use files with this extension

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

Visual BasicVisual BasicUser submitted
NewSoft CD LabelerNewSoft CD LabelerUser submitted
MiKTeXMiKTeXUser submitted
ExamViewExamViewUser submitted
TeXworksTeXworksUser submitted
progeCAD ProfessionalprogeCAD ProfessionalUser submitted
WinEdtWinEdtUser submitted
Microchip Application MaestroMicrochip Application MaestroUser submitted
TimetableTimetableUser submitted
MKEditorMKEditorUser submitted

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