diff-pdf is a tool for visually comparing two PDFs.
It takes two PDF files as arguments. By default, its only output is its return code, which is 0 if there are no differences and 1 if the two PDFs differ. If given the --output-diff option, it produces a PDF file with visually highlighted differences
Website: https://vslavik.github.io/diff-pdf/
Source: https://github.com/vslavik/diff-pdf/
Download: https://github.com/vslavik/diff-pdf/releases
Note: this repository is provided as-is and the code is not being actively developed.
(Author does accept pull requests for bug fixes, improvements)
Note it has a built-in PDF/result viewer as well but in essence a command line tool.
Reference: DiffPDF Gui tool/PortableApps version:
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