HHP File

What are HHP files and how to open them

Are you having problems opening a HHP 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 HHP files.

What is a HHP file?

A .HHP file is a Microsoft HTML Help Project file.

Microsoft HTML Help Project files are plain-text configuration files used during the creation of compiled HTML Help (.CHM) files. They are produced and written by Microsoft HTML Help Workshop (or compatible authoring tools) when you build a help project. Their purpose is to gather all the pieces - HTML topic files, image files, contents (table of contents), and index entries - then specify options such as window layouts, which files to include, and how the compiled help file should appear, before handing everything off to the HTML Help compiler.

These project files are edited by help authors: you list your HTML or HTM topic files, images (GIF, JPEG, PNG), contents file (.HHC), and index file (.HHK), set window definitions, default topics, display settings, and other options that change how the final CHM behaves. Once the .HHP is complete, the compiler uses it to build the single .CHM file that end users can open to view the help system.

Internally, the file is structured like an INI file, with named sections in square brackets such as [OPTIONS], [FILES], [WINDOWS]. It begins with a header like "[OPTIONS]" (ASCII) and contains keywords like COMPILED FILE, CONTENTS, INDEX, OPTIONS, with references to the .CHM file and often to .HHC/.HHK files. These identifiers help tools recognise it as an HTML Help project specification.

How to open HHP files

We have identified one HHP opener that is compatible with this specific type of HHP file.

Programs that open Microsoft HTML Help Project files

Last updated: August 7, 2026

Various apps that use files with this extension

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