Do my files get uploaded to compare them?

No — and that is the whole point. Every other compare tool uploads both documents to its servers to diff them, which means handing over two confidential versions at once. Here the PDFs are read and compared entirely in your browser, on your own device. Neither file ever leaves your computer or reaches a server; the comparison even works with your network disconnected.

What does it actually show me?

Two things per page. First, a word-level text diff: the words that were added are highlighted in green and the words that were removed are struck through in red, so you can read the exact change. Second, a visual change percentage measured from the rendered pages — this catches changes to images, stamps, and layout that the text can't show, and it also works on scanned pages that have no text at all.

Does it work on scanned PDFs?

Partly, and it tells you so honestly. A scanned PDF has no text layer, so the word-level diff can't run — the tool says the file looks scanned and shows the visual page comparison instead, rather than pretending there are no changes. For a word-level diff, both files need a real text layer (a normal digital PDF exported from an app).

It reports textual and visual differences, not a legal judgement about whether a change matters. It also aligns pages by position: if a paragraph moves to a different page, it is shown as removed from the old page and added to the new one, rather than tracked as the same paragraph relocated. That semantic layout tracking is a separate, much harder problem and is not claimed here.

PDF Tools

Compare PDF

Compare two versions of a PDF and see exactly what changed — the words added and removed on each page, plus a visual change indicator for images and layout — entirely in your browser. Neither file is uploaded: comparing two documents means exposing both, and this is the only way to do it without sending either to a server. No account, no email.

Frequently asked questions

Do my files get uploaded to compare them?: No — and that is the whole point. Every other compare tool uploads both documents to its servers to diff them, which means handing over two confidential versions at once. Here the PDFs are read and compared entirely in your browser, on your own device. Neither file ever leaves your computer or reaches a server; the comparison even works with your network disconnected.
What does it actually show me?: Two things per page. First, a word-level text diff: the words that were added are highlighted in green and the words that were removed are struck through in red, so you can read the exact change. Second, a visual change percentage measured from the rendered pages — this catches changes to images, stamps, and layout that the text can't show, and it also works on scanned pages that have no text at all.
Does it work on scanned PDFs?: Partly, and it tells you so honestly. A scanned PDF has no text layer, so the word-level diff can't run — the tool says the file looks scanned and shows the visual page comparison instead, rather than pretending there are no changes. For a word-level diff, both files need a real text layer (a normal digital PDF exported from an app).
What are its limits?: It reports textual and visual differences, not a legal judgement about whether a change matters. It also aligns pages by position: if a paragraph moves to a different page, it is shown as removed from the old page and added to the new one, rather than tracked as the same paragraph relocated. That semantic layout tracking is a separate, much harder problem and is not claimed here.

Frequently asked questions

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