Acrobat Preflight Tool allows to browse the internal structure of a PDF document. After starting the Preflight tool (Shift-Ctrl-X or Shift-Cmd-X on a Mac), look under the “Options” menu in the right top corner and select the menu item “Browse internal PDF structure”. This will bring up a new dialog that shows the internal structure of the PDF.

Unfortunately, there are some limitations:

  • Acrobat might change the PDF when it opens it. For instance it may generate appearance streams when they are missing.
  • It is not possible to copy file content
  • It is not possible to see actual string bytes after Acrobat parsing. You don’t see Unicode BOM prefix, etc…

Here are a couple PDF file structure viewers that can be used  to avoid these limitations:


iText RUPS (RUPS stands for Read and Update PDF Syntax)

qPDF (for the real hard cases…)