Spot the differences between two PDF files, page by page.
Upload two PDFs, flip through pages side by side, or highlight the pixel differences.
Is this tool really free?
Yes. Every tool on this site is free, with no account or sign-up required.
Are my files uploaded to your servers?
No. All processing happens in your browser, so your files never leave your device.
What if the two PDFs have different page counts?
Pages are compared one by one, up to the shorter document. Extra pages in the longer file are shown on their own.
Comparison puts two PDFs side by side, page by page, and marks what differs. Flip through pages with Previous and Next, zoom in to inspect details, or switch to Highlight differences to see changed areas marked in red. The sensitivity control sets how small a difference counts as a change.
Start with the side by side view to find the pages that differ, then zoom in on the details. Highlight differences is the fastest way to scan a long document: unchanged pages stay clean, changed areas show up in red.
It shows pixel differences, not meaning. Reworded text, a moved paragraph and a changed font all show up as changes, and it cannot tell you which version is correct. It also does not merge or edit either file. Both originals stay untouched.
Can I compare scanned PDFs?
Yes. Scanned pages compare as images, so any pixel change shows up.
What does sensitivity do?
It controls how small a difference is flagged. Adjust it if tiny marks are flagged or real edits are missed.
Does comparing change my files?
No. Both originals stay untouched.
Read our step by step guide: How to Compare Two PDF Documents.