Kchmviewer - Kchmviewer is a free, open-source CHM (MS HTML help) and EPUB viewer for Unix, Mac and Windows...
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request
WinCHM - Creating CHM file, Make CHM file, Web Help. WinCHM Pro - Help authoring software (CHM, WebHelp, DOC, PDF) . With this powerful tool you can not only create chm file from scratch, but also convert a set of existing HTML files to a chm file.
DocRaptor - As the only API powered by the Prince HTML-to-PDF engine, DocRaptor provides the best support for complex PDFs with powerful support for headers, page breaks, page numbers, flexbox, watermarks, accessible PDFs, and much more
Read CHM - Read CHM is ultimate CHM (Compiled HTML Help) file reader.
PDFCrowd - Pdfcrowd is a Web/HTML to PDF online service. Convert HTML to PDF online in the browser or in your PHP, Python, Ruby, .NET, Java apps via the REST API.