PDF Merge Tool is one of the best merger and combine solution for users who want to learn how to add 2 PDF files in one PDF file. During the conversion process, it maintains all the properties and structure of PDF files to effortlessly manage the combine files. Batch mode is also delivered by this software at a single round. Free download version of this tool is also given by the software for users so that they to easily understand the working procedure of how to add 2 PDF files in one PDF file. But it allows to add first 5 PDF files with CubexSoft watermark.