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Compress PDF

Compare PDF

Compare two PDFs and see differences in their pages and text. Your files never leave your device — all processing happens locally in your browser.

Private by design
Your files never leave your device. All processing happens locally in your browser — no uploads, no servers.
Document A (original)

Drop your PDF here

or click to choose a file

Your files never leave your device.

Document B (revised)

Drop your PDF here

or click to choose a file

Your files never leave your device.

Choose two PDFs to compare. Differences in page count and extracted text are reported privately in your browser — your files never leave this device.

Compare PDF extracts the text of two PDFs page by page with PDF.js and reports page-count differences, added or removed pages, and word-level changes on pages that differ. The comparison runs in a Web Worker, so neither file nor extracted text leaves your device. It compares text content — not rendered pixels — and says so plainly.

How it works

How to use Compare PDF

  1. 1
    Add both PDFs. Drop the original document and the revised document into the two slots.
  2. 2
    Run Compare PDF. PDF.js extracts each page's text locally and the diff aligns pages by number.
  3. 3
    Review the differences. See which pages are identical, changed, added or removed, plus the words added and removed on changed pages.

Features

What this tool does

  • Page-count and page-alignment report
  • Changed, added and removed page status
  • Word-level additions and removals on changed pages
  • No upload — both documents stay on your device

Limitations

Things to know

  • Text comparison only — a pixel-perfect visual diff is not performed
  • PDFs without a text layer compare as empty text and cannot show content changes
  • Layout or image changes that do not alter text are not reported
  • Encrypted PDFs must be unlocked before comparison

FAQ

Frequently asked questions

Is this a visual comparison?

No. It compares extracted text page by page. A re-layout that keeps the same words may not be detected, and scanned pages without a text layer cannot be compared.

Are my documents uploaded?

No. Both PDFs are processed in a Web Worker on your device. File names and extracted text are never sent to a server.

Why does a page show as changed when it looks the same?

Text extraction can differ because of whitespace, hyphenation, fonts or hidden text. The word-level summary shows exactly what the diff detected.

Can I compare password-protected PDFs?

Not directly. Unlock both PDFs first, then compare the decrypted copies.