PDF Joiner - This online tool allows you to join several PDF documents into a single file, free of charge.

PDF to JPG - PDF to JPG is used to convert PDFs to JPG, PNG, BMP, TIF, GIF, PCX and TGA images in batch mode. It works without Adobe Acrobat or Adobe Reader, and has Command Line Interface (CLI), fast and accurate conversion ability, friendly GUI, small size.

DocuPUB - DocuPUB is an online file converter, file merger, file compressor, and file resizing tool.

UnityPDF - UnityPDF lets you merge, split, divide, rotate, protect PDF files and more.

PDFChef Merge PDF - PDFChef Merge PDF is an online tool that allows you to merge multiple PDf files into one quickly and securely.

PDFsam - PDFsam Basic, a free, open source, multi-platform software designed to split, merge, extract pages, mix and rotate PDF files