HLP is WinHelp, the help format of Windows 3.0 to XP: the manuals of countless older programs, games, drivers and shareware, and whole books and magazines published as help files. Windows 10 and 11 no longer include WinHlp32, so double-clicking a .hlp file only brings up a message about a feature that is not supported, and Macs, Linux and Chromebooks never could open them.
This page decompiles the file with helpdeco, the open-source WinHelp decompiler, compiled to run in your browser, and shows it as WinHelp did: topics with their fonts, colours and pictures, jumps between topics, popup definitions, clickable hotspots on pictures, the contents (from the .cnt file, if you add it), the keyword index and a search through every topic. Pictures with hotspots and vector pictures (WMF) are converted for the browser here. Print a topic, a chapter or the whole book, or save it as a PDF, as Markdown or as plain text, or get the decompiled RTF and project file back. It is free to use, with no account and no upload limit, and it runs entirely in your browser: nothing is uploaded, and while the page stays open, a feature you have already used keeps working offline.
- Why won't Windows 10 or 11 open .hlp files?
- Microsoft stopped shipping WinHlp32, the WinHelp viewer, with Windows Vista, and offered it as a separate download only up to Windows 8.1. On Windows 10 and 11 there is no official viewer at all. This page needs nothing installed.
- How do I convert an HLP file to PDF?
- Open it here, choose Whole book (or a chapter) beside Print or save as PDF, and pick "Save as PDF" as the printer. Topics come out in contents order, each starting on a new page, with their pictures, as text that can be searched.
- What is the .cnt file for?
- WinHelp 4 (Windows 95 and later) kept the contents tree in a separate .cnt file beside the .hlp. Without it the page lists every topic in order, which still works for reading and searching; with it you get the chapters and sections the author arranged. Older help files have no .cnt.
- Does everything in the help file work?
- Text, formatting, pictures, jumps, popups, hotspots, keywords and the contents all do. Macros that ran programs or changed WinHelp's buttons, links into other help files, and embedded windows or videos are not run; their text still shows. Damaged parts of a file are skipped, and the page says so.
- Can I get the original help sources back?
- Yes, as near as can be: Decompiled sources saves the RTF topic file, the help project (.hpj), the pictures and any phrase table, which Microsoft's help compiler can build into a working .hlp again. Topic names that the compiler hashed away come back as made-up names that point to the same topics.