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Compare Two PDFs

Compares the text of two documents line by line and reports what was added and what was removed, as a plain report you can read or file.

Local processingAccepts PDFUp to 100 MBUp to 20 files

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PDF · up to 100 MB each · you can also paste from the clipboard

Nothing is processed until you press the button below.

How this tool works

  1. 1The text layer of each document is extracted.
  2. 2Lines are compared after collapsing whitespace, so reflowed spacing does not register as a change.
  3. 3Added and removed lines are reported separately, with a similarity figure.

What it will not do

  • This compares words, not appearance. Two documents with identical text but different fonts, spacing or images will be reported as the same.
  • A line that merely moved will not be reported. A line whose wording changed appears twice, once on each side.
  • Scanned documents have no text to compare. Run OCR on both first.

Where this runs

Compare Two PDFs runs entirely inside this page. Your file is read by the browser, processed in memory and handed back to your downloads folder. It is never sent to a server, because there is no server involved in this tool.

Read the full processing model →