DiffPDF

DiffPDF is a tool to compare two PDF files via three different means: by word, by number of characters, or by appearance. It's a highly useful app to not lose track of the final version when you're constantly saving different versions of the same file.

This comparator application will analyze two PDF documents in order to detect the differences between them. DiffPDF can review a whole document as well as specific pages or different intervals.

How does it work? Just select the documents you need to compare and the type of analysis you wish to do, either by text or image. Click on 'Compare', and DiffPDF will highlight all the differences between the files.

In addition, DiffPDF doesn't need to be installed: you can use the software wherever you need to just by storing it on a USB drive.