Question 1

How is this different from Word's Track Changes?

Accepted Answer

Word's Track Changes requires both parties to be using Word and to have kept change tracking enabled throughout every edit. If a collaborator edits without it on, accepts all changes, or sends you a fresh PDF, the audit trail is lost. Contract Redline works on final artifacts — drop in any two versions of a contract (even as PDFs after a round trip through signing software) and we reconstruct the redline from the actual text.

Question 2

Does it work on PDFs or only Word files?

Accepted Answer

Both. Drop PDF or DOCX files in either slot, and you can mix — compare a PDF against a Word doc, or two PDFs against each other. We extract text via pdf.js for PDFs and mammoth for DOCX, then run the diff on the extracted text.

Question 3

Will it detect moved paragraphs?

Accepted Answer

Moved paragraphs show as a deletion in one place and an insertion in another — the diff algorithm is line-by-line so a paragraph moved from page 2 to page 5 appears as two entries. This matches how DocuSign Rooms and most contract-review tools handle moves. If move-detection is critical, combining the redline with the original document layout (via side-by-side reading) usually makes the intent obvious.

Question 4

Is my contract uploaded to a server?

Accepted Answer

No. Both files are parsed locally in your browser. pdf.js handles PDF text extraction entirely client-side; mammoth does the same for DOCX; the diff runs in-browser JavaScript. No uploads, no server side processing, no record kept of your document contents. This matters especially for contracts containing sensitive commercial terms.

Question 5

Does it handle scanned contracts (images of text)?

Accepted Answer

Not directly — the tool extracts the PDF's text layer, which scanned PDFs don't have. First run your scanned PDF through our PDF OCR tool to generate a searchable text layer, then feed the OCR'd result into Contract Redline. Note that OCR errors can introduce false differences between the two compared files, so review the OCR output before comparing.

Question 6

Can I export the redline?

Accepted Answer

Yes. Export as an HTML file that preserves the red/green highlighting — you can open it in a browser, email it, print to PDF, or share as-is. The output is styled for screen and print, and keeps the insertions/deletions/unchanged formatting so a reviewer can scan through quickly.

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