diff PDF
Compare two PDF files and show the differences.
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What is diff PDF?
diffPDF is an open-source tool designed to visually compare two PDF documents, identifying differences in content, formatting, or layout. It serves as a command-line utility that analyzes PDF files and provides output indicating whether they are identical or highlights discrepancies. The tool is particularly useful for users needing to verify document accuracy, track changes between versions, or ensure consistency across files. Its primary audience includes developers, researchers, and professionals in fields like legal, academic, or technical documentation where precise document comparisons are critical. By automating the comparison process, diffPDF saves time and reduces the risk of human error in manual reviews.
How it works
diffPDF is a GPL-licensed open-source project that enables users to compare two PDF files for differences. It operates via the command line, offering a straightforward method to assess document changes without requiring complex software. The tool addresses the need for reliable, automated comparison of PDFs, which is essential in scenarios such as version control, document validation, or audit trails. Its output can be a simple exit code or a detailed visual comparison, depending on user options. diffPDF supports two primary modes: a command-line exit code that returns 0 for identical files or 1 for differences, and a --output-diff option that generates a new PDF with highlighted discrepancies. The --view argument opens a GUI for manual page-by-page comparison, allowing users to zoom and inspect details.
How to use it
- 1Install the tool from its GitHub repository. 2. Use the command-line interface to run diff-pdf with two PDF files as arguments. 3. Add --output-diff=filename.pdf to generate a comparison document. 4. Use --view to launch the GUI for interactive page-by-page analysis. Practical tips include ensuring both PDFs have matching page counts and layouts for accurate comparisons. The tool requires command-line proficiency and may need dependencies like Qt for the GUI.
What it can do
- pdf comparison
Use cases
Assumptions and limitations
Assumptions
- source: https://github.com/vslavik/diff-pdf
- license: GPL-2.0 — free to use
- privacy: Self-hosted — you control your data
Limitations
- The project is not actively maintained, with no guarantees for bug fixes or feature updates
- Limited support for complex PDF features like embedded fonts or encryption
- GUI mode requires Qt dependencies, which may not be available in all environments
- Does not compare metadata, bookmarks, or annotations between files
- Output PDFs with highlighted differences may require additional tools for detailed analysis
Understanding the result
Compare two PDF files and show the differences.
Tool details
- Clearly flagged when a network request is needed.
- No account, no sign-up, and no tracking of your content.
- Powered by (MIT).
- Built with
- (vslavik/diff-pdf)
- License
- MIT
- Runs locally
- No — requires a network request
- Verification
- Not yet verified
- Input
- Query
- Output
- Text
Built with vslavik/diff-pdf. OpenToolVault provides the discovery and browser interface while crediting the original project maintainers.
- Built with
- License
- MIT
Open-source project
OpenToolVault is an independent directory. We are not affiliated with or endorsed by this project.
References
- / — GitHub Repository
Upstream project · GitHub
- GPL-2.0 License
Upstream project
Frequently asked
What file formats does diffPDF support?
diffPDF specifically handles PDF files. It does not support other document formats like Word or Excel. The tool focuses on comparing text, images, and layout within PDFs, ignoring metadata or embedded objects.
How does diffPDF detect differences between PDFs?
The tool parses the raw content of PDF files, comparing text, images, and layout elements page by page. It uses algorithms to align pages and identify visual discrepancies, such as modified text or repositioned graphics. However, it does not analyze metadata or interactive elements like form fields.
How do I generate a PDF with highlighted differences?
Use the --output-diff=filename.pdf option followed by the two PDF files. For example: diff-pdf --output-diff=diff.pdf document1.pdf document2.pdf. The resulting file will visually mark added, removed, or modified content.
How does diffPDF compare to commercial tools like PDFdiff or PDF-XChange?
diffPDF is open-source and free to use, while commercial tools often offer advanced features like side-by-side comparisons or integration with document management systems. Unlike PDFdiff, diffPDF lacks a graphical interface by default, and PDF-XChange provides more detailed formatting analysis. diffPDF is better suited for developers or users comfortable with command-line workflows.
What should I do if diffPDF returns an error about missing dependencies?
Ensure all required libraries, such as Qt for the GUI mode, are installed. Check the project's README for system-specific dependencies. If using the GUI, verify that your environment supports Qt frameworks. For command-line errors, confirm the correct file paths and permissions for the PDFs being compared.