Is Compare PDF free?
Yes. This tool is free to use with no sign-up, and it runs entirely in your browser.
Are my PDFs uploaded to a server?
No. Both PDFs are compared locally in your browser, so the files stay on your device.
Does it export an annotated diff PDF?
No. This version provides on-screen analysis only, so it shows the differences rather than producing a redlined file.
Can it compare scanned PDFs?
It can still run visual page checks on scanned PDFs, but the text diff is strongest when the pages contain selectable text.
What kinds of differences does it find?
It detects changed text, visual differences on a page, and pages that were added or removed between the two documents.
Does it compare how the pages look?
No, and usually you should not want it to. Two exports of the same document from different machines can differ visually while being identical in content. This compares the text.
Why does it show so many changes after one edit?
Reflow. Inserting a sentence shifts everything after it, so a single edit can look like a rewritten section. Read the comparison with that in mind.
Can it compare two scanned PDFs?
No. There is no text layer to compare. OCR them first, and expect the comparison to inherit every OCR mistake.
Will it tell me which changes matter?
No. A changed figure in a contract and a changed comma look the same to it. It finds differences; judging them is your job.
Are my documents uploaded?
No. Both stay in your browser, which is precisely why this is a reasonable place to compare two drafts of a contract.
Can it merge the changes?
No. It shows you what differs; it does not accept, reject or merge anything.