CPTX File

What are CPTX files and how to open them

Are you having problems opening a CPTX 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 CPTX files.

What is a CPTX file?

A .CPTX file is a Captivate Project file.

A Captivate Project file stores a full multimedia e-learning project built with Adobe Captivate. It holds content such as slide layouts, screen recordings or simulations, interactive quiz elements, text, images, audio, video, and navigation logic. This format is used to author and edit e-learning materials before publication.

The file is written and updated by Adobe Captivate (version 5 and newer). After saving a project, Captivate users can reopen it, modify its slides or interactions, preview how it will look, and then publish the project into final deliverables (such as HTML5, MP4 video, executable files, or LMS-compatible content). Captivate Classic (.cptx) projects can be imported by newer versions (for example Captivate 13.1 beta) to migrate existing content into a non-responsive project framework.

Internally the format is based on a compressed archive (ZIP-style) containing structured sub-folders and files that represent each part of the project: media, audio, text, objects, thumbnails, and slide-specific data. A typical file signature is the ASCII bytes "PK" at offset 0, along with folder/file names like "info.cpi", "audio.cpad", "text.cptd", "objects.cpo", "thumbnails.cpth", and string markers such as "UNCOMPRESSED_DATA" or "PREVIEWTHUMBNAIL.CPTHPK".

How to open CPTX files

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

While we have not verified the apps ourselves yet, our users have suggested four different CPTX 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 CPTX files. Remember, different programs may use CPTX files for different purposes, so you may need to try out a few of them to be able to open your specific file.

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