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🔍 Compare PDF Files

Upload two PDFs and see exactly which lines were added, removed, or changed on every page. Free, in your browser.

Compare Two PDFs

🔒 Both files are compared entirely in your browser — nothing is uploaded.

How It Works

1
Upload the original and revised PDF
2
Click Compare PDFs
3
Review line-by-line differences, page by page

Why Compare PDF Files

Contracts get redlined, reports get revised, quotes get amended — and spotting exactly what changed between two versions by eye is slow and error-prone, especially across many pages. This tool extracts the text from both files and highlights every added and removed line on each page, so you can review a revision in minutes instead of scanning line by line yourself.

⏱️ Last Updated: August 2026 | Mohsin Iqbal | Free browser-based tools — no upload required
🛡️ 100% Private
⚡ No Upload
💻 Browser-Based
🔒 Free Forever

🔑 Key Takeaways

  • Compares two PDFs page-by-page and line-by-line
  • Highlights added, removed, and unchanged lines
  • Text-based comparison — doesn't catch purely visual/formatting changes
  • Pages are matched by position, not content
  • 100% private: both files compared entirely in your browser

What Does "Compare PDF Files" Do?

This tool reads the text content of every page in both PDFs, matches pages by their position in each file (page 1 to page 1, and so on), then runs a line-level difference calculation on each matched pair — the same underlying approach as a code "diff" tool, applied to document text. Lines only in the revised file are marked added, lines only in the original are marked removed, and everything else is shown unchanged for context.

Because it compares text, not pixels, it will catch wording changes reliably but won't flag a purely visual change — a different font or a swapped image with the same caption — since the underlying text is unchanged.

Good Fit vs Not a Good Fit

Good forNot a good fit for
Contract redlines and revised clausesDetecting a font, color, or layout-only change
Quote/proposal amendmentsDocuments where pages were inserted or reordered
Spotting wording changes between report draftsScanned/image-only PDFs with no real text layer

Frequently Asked Questions

How does this tool compare two PDFs?

It extracts the text of each page from both files, matches page 1 against page 1, page 2 against page 2, and so on, then runs a line-by-line comparison on each pair — showing which lines were added, removed, or are unchanged.

Does it compare visual layout, or just text?

Text content only. It won't catch a change that's purely visual — like a font, color, or image swap — with no change to the actual words on the page.

Are my PDFs uploaded to a server?

No. Both files are read and compared entirely inside your browser using pdf.js — neither file is transmitted anywhere.

What happens if the two PDFs have a different number of pages?

Pages are compared by position (page 1 vs page 1, page 2 vs page 2). Any extra pages at the end of the longer file are shown as entirely added or removed content, since there's no matching page on the other side.

What if a page was inserted in the middle, shifting everything after it?

Since pages are matched by position rather than content, an inserted page will make every following page look completely different from its counterpart, even if the actual content only shifted. For documents where pages might be inserted or removed, review the summary carefully rather than assuming position-matched results.

Can I compare Word documents this way?

This tool reads PDF files specifically. Save or export your Word documents as PDF first, then compare the two PDFs here.