Redline Comparison (Track-Changes Style)
Compare two PDFs and produce an inline-redline report — deleted text struck through in red, inserted text underlined in green.
1. Upload your files (min 2)
How does the Redline Comparison (Track-Changes Style) work?
Compare two PDFs and produce a clean redline report in classic legal track-changes form: removed text drawn in red with a strikethrough line, newly-inserted text drawn in green with an underline. Files are paired alphabetically by name (so name them sensibly — "v1-old.pdf" and "v2-new.pdf"), then diffed page-by-page using a line-level alignment. The output is a single PDF with a cover summary plus one page per page-of-comparison. Use Compare Two PDFs (the existing tool) if you want a side-by-side per-page split instead of inline redline.
🔒 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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