Compare PDFs Visually - Free Online Browser Tool

Overlay two PDF pages to highlight visual differences.

The fastest way to see what changed between two PDFs is to look at them together. This tool overlays two pages — aligned and blended — so differences in layout, spacing and imagery are obvious at a glance rather than requiring careful reading of both documents.

This compare pdfs visually utility runs completely inside your web browser. Your document is opened locally and processed on your own device using JavaScript and WebAssembly, so your file is never uploaded to any server. There is no signup, no watermark and no limit on how many documents you can handle.

  • 100% client-side - files never leave your device
  • Instant processing, no upload wait
  • Works on desktop, tablet and mobile
  • Free forever, no account required

Common next steps: Compare Extracted Text, High-Res Page Inspector, Find Duplicate Pages.

How to Use the Compare PDFs Visually Tool

Four steps, and the whole thing runs locally on your own device.

  1. Add both documents

    Drop in the original and the revised version. The first becomes the base layer.

  2. Pick a page from each

    Select which page pair to compare. You can move through matching pages one at a time.

  3. Adjust the overlay

    The blend opacity controls how much of each document shows, so you can isolate one layer or superimpose both.

  4. Review the differences

    Layout shifts, moved images and changed spacing are immediately visible in the blended view.

Frequently Asked Questions

What can an overlay show that a text diff cannot?

Visual change: a shifted image, a resized box, altered spacing or a moved table. A text comparison would show identical characters in a completely different layout and call it no change.

How is this different from Compare Extracted Text?

Text comparison reports differences in the words themselves. This compares the rendered pages, so it catches layout and formatting changes that text comparison is blind to.

Does the comparison work on scanned documents?

Yes, because it compares rendered images rather than text. That makes it useful for comparing signed or scanned versions of a document.

Do I need both documents to have the same page count?

No. The tool will compare up to the matching page numbers and tell you if one document has pages the other lacks.

Is either document modified?

No. This is a read-only comparison operation and nothing is written back to either file.