Compare Two PDFs
Find what changed between two PDFs — text-level diff, page by page, output as a side-readable report.
1. Upload your files (min 2)
How does the Compare Two PDFs work?
Compare two PDFs and find out what changed. The tool extracts the text from both, runs a line-level diff on each page (using LCS — the same algorithm git diff uses), and emits a report PDF: cover page with totals and a per-page summary, then one section per page showing additions in green (+) and removals in red (−). The first PDF (alphabetically) is treated as the older version (A); the second is the newer (B). Use this when reviewing redlines, comparing a draft to a published version, or auditing what a PDF rewrite actually changed. Conversion runs in your browser; both files stay on your device.
🔒 Security & Privacy
All processing happens on your device. Your files never leave your browser, never touch our servers, and are not stored anywhere. Close the tab and the file is gone.
📱 Use it on any device
Works in any modern browser — Mac, Windows, Linux, iPhone, Android, and tablets. No installation, no app to download. Just open the page and start.
⚡ Quick & easy
Drag, drop, click. Most files process in seconds, not minutes. No watermarks added to your output, no per-day limits, and the tool always shows the result before asking you to download.
🎁 Always free, no signup
Free to use, every time. No account creation, no email required, no “trial” that converts to a paid plan. We make money from ads so you don’t have to pay.
Frequently asked
For heavier PDF workflows
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