Does it compare the text or the look?

The look. It detects visual differences on each page, which catches edits, moved content, and formatting changes, not just text.

Do both files ever leave my device?

No. Both PDFs are rendered to canvas and compared pixel by pixel in this tab; neither one is sent anywhere to make the comparison.

Compare PDFs

No upload · runs in your browser

Original (A)Drop a PDFSelect files No upload · processed locally · auto-deletedRevised (B)Drop a PDFSelect files No upload · processed locally · auto-deleted

How it works

How to compare two PDFs without uploading

Drop two versions of a document and FernPDF renders both in your browser, then flags every page that changed, plus any pages added or removed. A fast way to review edits between drafts.

Because both files are compared locally, confidential contracts and revisions are never uploaded to a server.

FAQ

Both PDFs are rendered page by page in your browser and compared visually. Pages that differ are flagged, along with pages added or removed between the two versions.

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