PDF Comparator uses Mac OS X’s built-n ability to render PDF files to compare two PDFs, page by page, and pixel by pixel. It then displays the results in an intuitive and easy to understand display. PDF Comparator provides lots of control over how the PDFs are rendered for comparison including resolution, which PDF “box” to compare, and the sensitivity of how different two pixels must be to be considered “different.” PDF Comparator is a great tool for PDF content creators who need to be sure that a PDF file contains all the changes that were supposed to be made (and none that were not).