Are my PDFs uploaded when I compare them?

No. Comparison runs entirely in your browser with PDF.js and optional on-device OCR. Files never leave your device.

Why does comparison take a long time?

Large documents, many pages, or OCR on scanned pages increase processing time. Everything still runs locally on your machine.

What is page pairing?

When page counts differ, SagePDF aligns pages using text signatures so you can compare drafts that gained or lost pages.

What does the HTML report contain?

A downloadable summary of text differences per paired page, useful for sharing or archiving review results.

Compare PDFs Online Free

Compare two PDFs side by side. All processing happens in your browser. No uploads, no signup—your files never leave your device.

How to use

Upload two PDFs

Add the original PDF and the revised PDF. Both files stay in your browser—nothing is uploaded.

Review differences

Pages are paired automatically. Use overlay or side-by-side view, filter by added/removed/modified text, and step through changes. Optional OCR helps with scanned pages.

Export report (optional)

Download an HTML report summarizing differences across all paired pages.

Frequently asked questions

Merge PDF
Combine whole files, or select specific pages to merge into a new document.
Split PDF
Extract by range, even/odd, every page, visual selection, bookmarks, or every N pages—all in your browser.
View Metadata
Inspect the hidden properties of your PDF.