Every changed word, in plain sight
Word by word
A changed rent amount, a new clause or a missing line all show up, with the old text struck through and the new text underlined.
Pages side by side
See both versions next to each other with the changes marked on the page. Text that only moved to the next page isn’t counted as a change.
Private by design
Your browser reads and compares the files. Agreements, salary letters and bank forms never leave your phone or computer.
How to compare two PDFs
Choose the old version
Drop the earlier copy in the Old version box, or tap Choose a PDF.
Choose the new version
Add the copy you want to check in the New version box. Got them the wrong way round? Press Swap old and new.
Compare
Press Compare PDFs. Your browser reads every page and finds the differences, usually in a few seconds.
Check the changes
Go through the list of changes, or switch to Side by side to see them on the pages. Download the report to keep a copy or share it.
Questions
Are my files uploaded anywhere?
No. Both PDFs are read and compared inside your web browser, so they stay on your device. Nothing is sent to us or anyone else.
What exactly does it compare?
The words in the two PDFs, in reading order. Added, removed and changed words are shown with a few words around them and the page they are on. Spacing and line breaks are ignored, and so are curly versus straight quotes, so a re-typed document doesn’t show false changes.
Does it spot changes to images, signatures, stamps or formatting?
No. Only the text is compared. A new photo, a moved signature, a different font or colour, or bold text won’t show up. Use the side-by-side view to look over the pages yourself for those.
It says my PDF has no text. What should I do?
That PDF is a scan, which is just pictures of the pages. Run it through Scan to text (OCR) first to add the text, then compare the new file here. OCR can misread a few letters, so treat small differences in a scanned copy with care.
The versions have a different number of pages. Does that matter?
No. The whole document is compared in one go, and pages are lined up by matching text. If a clause pushes the rest of the text onto a new page, only the clause counts as a change.
Can I compare password-protected PDFs?
If the PDF asks for a password to open, remove the password first with Unlock PDF, then compare. PDFs that only block printing or copying can be compared as they are.
How big can the files be?
Up to 100 MB each. Long documents with hundreds of pages work too; reading them takes a little longer, and you can see the progress page by page.
Does it cost anything?
No. Compare PDFs is free and needs no account.