Compare PDFs
Highlight the differences between two versions of a PDF.
- 100% Private
- No Limits
- Works Offline
or drag and drop here
Spot every difference between two versions of a PDF document side by side. Highlights changes page by page right inside your browser so you never miss an edit or unexpected modification, all without uploading your documents anywhere.
How to Use Compare PDFs
- 1
Upload both PDF versions
Add your original document first and the updated revision second.
- 2
Compare pages
Click Compare PDFs to analyze differences page by page locally in your browser.
- 3
Review changes and download
See which pages were modified, added, or removed, and download a visual diff PDF.
Why Choose PurePDF for Compare PDFs
Nothing leaves your device
Comparison runs entirely in your browser tab, ensuring confidential drafts and legal files stay private.
Clear visual highlights
Modifications are clearly marked on the revised pages so you can see exact edits instantly.
Page-by-page status
A summary breakdown shows exactly which pages are identical, modified, added, or deleted.
Common Use Cases for Compare PDFs
Contract revisions
Catch unexpected changes, updated clauses, or altered numbers between drafts before signing.
Design & layout proofs
Verify that layout updates, image replacements, and typography tweaks are positioned correctly.
Document auditing
Ensure that an exported final document contains only the approved edits from earlier rounds.
Pro Tips for Compare PDFs
- The first file you upload is treated as the original and the second as revised — drag thumbnails to reorder if needed.
- Documents with matching page sizes and orientations produce the clearest visual comparison.
- Check the page summary badges to jump straight to modified pages rather than reviewing matching ones.
Frequently Asked Questions About Compare PDFs
Will my PDF file be uploaded to a server?
No — nothing is uploaded. This tool runs entirely in your browser via WebAssembly/JavaScript; your file never leaves your device.
Is there a file-size limit, a usage cap, or a hidden fee?
It's free and unlimited, with no watermark and no forced file-size cap — the only real limit is your own device's memory for very large files.
Do I need to create an account or sign up?
No — no account, email, or sign-up is required for any tool. Just start using it.
Can I use this on my phone (iPhone or Android)?
Yes — it works in any modern mobile browser, no app install needed.
Which file is treated as the original document during comparison?
The first file you upload is treated as the original and the second as revised; you can drag thumbnails to reorder them if needed.
How are page modifications highlighted?
Changes are visually marked on revised pages, and summary badges show whether each page is identical, modified, added, or deleted.