HelpNDoc allows the writer to create a single source text which it then converts to a number of target formats such as HTML Help, PDF, RTF, DocX, Qt Help, and HTML documentations as well as EPUB and Amazon Kindle compatible E-books. HelpNDoc integrates a WYSIWYG editor which aims to look like popular word processing software such as Microsoft Word or OpenOffice.org Writer. HelpNDoc has the ability to include variables and external files. It also has the ability to generate code for the C++, Delphi, Fortran, Pascal and Visual Basic programming languages for integration of the generated CHM help files with the application being developed. As of version 4 HelpNDoc comes with a project analyzer that can track the document’s layout, provide statistics and identify potential problems such as broken links or problems with media items. HelpNDoc can also be used to publish mobile websites, using the table of contents as a navigation menu, the content of the topics with navigation buttons, the keyword index menu, a built-in search engine, and mobile-specific user interface elements.
HelpNDoc's licensing model offers a free version of the program (Personal Edition) for personal use and two paid versions (Standard and Professional Editions) for commercial use. The free version includes an advertisement at the bottom of each generated documentation page, while the Professional Edition does not. The Standard Edition removes those ads from the CHM- and HTML-generated documentation.
HelpNDoc 1.0 was released to the public in December 2004 and only provided CHM and HTML documentation generation, while version 2.0 was officially released on May 2009 and introduced PDF and RTF documentation generation. The last version, 4.9, was released in January 2016.