PDF compare

Compare any two PDFs.

Upload two versions of a document and see every text difference — page by page, in your browser.

Original PDF
Drag and drop, or click to browse
PDF files — up to 20 MB
Edited PDF
Drag and drop, or click to browse
PDF files — up to 20 MB
Reading… PDFs stay in your browser — never uploaded
Comparison results PDF
This PDF appears to be scanned
We can only compare PDFs that contain selectable text. If you can't select text in the PDF, it's likely a scanned image. For scanned PDFs, try comparing pages visually.
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Change 1 of 1
These documents are identical
No text differences found. Every word and page break matches between the two PDFs.
Explain these changes in plain English
Pro summarises what changed across pages. "The pricing table on page 4 has new tier names and updated rates, and the cancellation policy on page 7 was rewritten."
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How does PDF comparison work?

ChangeChecks lets you compare PDF online for free, with no signup. Upload two PDFs — contracts, policies, reports, research papers — and we extract the text from each and show every difference between them. The merged view reads like a track-changes draft, with numbered markers so you can step through each change.

Because the text extraction and comparison both happen in your browser, the PDFs never leave your device. That is the right choice for legal, HR, and financial documents where uploading to a third-party service would create exposure. The page count, summary bar, and similarity score give you the at-a-glance view, then you drill into each change as needed.

If you have ever needed to see what changed in a PDF without printing both versions and comparing line by line, this is the same workflow as Track Changes — but for any PDF, without Word, without Adobe, and without an account.

Frequently asked questions

Are my PDFs uploaded anywhere?

No. Both files stay on your device; the text extraction and comparison run in your browser.

Can I compare scanned PDFs?

Only if the scan has an OCR text layer. Image-only scans need to be OCR'd first.

What if my PDF has images or tables?

Text only. The comparison works on extracted text; images and complex tables are not compared visually.

Is there a file size limit?

Yes, a soft one. Most PDFs under 50 MB process in seconds; very large files may take longer or hit your browser's memory limits.

Will it preserve the original layout?

No, we extract the running text. For layout-aware comparison, exporting to Word and using the document compare tool is sometimes better.

Learn more

How to see what changed in a PDF
Upload, scan the summary, navigate every difference with confidence.
For legal teams
Spot every clause that changed in a revised agreement.