How to compare two PDFs and find the differences

When you get a revised contract or report, finding what changed by eye is slow and error-prone. Compare PDF reads the text of both files and shows the differences line by line.

Steps

Open Compare PDF. Go to the tool.
Add the two files. Upload the original and the revised PDF.
Run the comparison. The text of both files is extracted and compared line by line.
Review the differences. Check the added and removed lines in the result.

Open the tool: Compare PDF

Good to know

It compares text only. Changes to layout, images or formatting are not detected.
A scanned PDF has no real text, so run it through OCR PDF first.
Each file is limited to about 4,000 lines of text.

Frequently asked questions

Does it detect changed images?

No. Compare PDF checks text, not visual layout or images.

Can I compare scanned documents?

Only after making them searchable with OCR PDF.

How many files do I need?

Two: the original and the new version.

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