Visual Diff (Image-based)
Compare two PDFs visually — rasterise each page, overlay the two as red/green channels, and produce a PDF that highlights pixel differences.
1. Upload your files (min 2)
How does the Visual Diff (Image-based) work?
Compare two PDFs at the pixel level. Each page from both files is rasterised at 1.5×, the pixel values are diffed, and the result is a new PDF where every page shows where the two differ (red pixels) on top of a faint grey rendering of the older version. Different from text-based comparison (Compare Two PDFs / Redline Comparison) — visual diff catches anything: text, images, layout shifts, stamp positions. Useful for proof-reading layouts where the text is identical but something visual moved.
🔒 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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