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Compare PDFs

Compare two PDF documents side by side and identify differences. See what text was added, removed, or changed between document versions.

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100% Private
Instant Processing
Browser-Based

Features

Compare two PDF documents
Highlight added text in green
Highlight removed text in red
Show unchanged text
Calculate similarity percentage
Export diff as HTML or text
Works with multi-page PDFs
Fast text extraction
Powered by PDFSub Engine
Files encrypted during transfer, auto-deleted after processing

How It Looks

Document A

Version 1

Document B

Version 2

How It Works

1

Upload the original PDF document

2

Upload the modified PDF document

3

Our tool extracts and compares the text

4

View the differences highlighted by type

Common Use Cases

Comparing contract revisions
Reviewing document changes
Tracking edits in legal documents
Verifying document updates
Auditing policy changes
Comparing report versions

Frequently Asked Questions

What kind of differences can be detected?

The tool detects text that was added, removed, or remains unchanged between the two documents. It compares line by line and highlights the differences.

Does it compare formatting or just text?

Currently, the tool compares text content only. Formatting changes like fonts, colors, or layout are not detected.

Can I compare scanned PDFs?

Scanned PDFs need to have embedded text (OCR) for comparison. If your PDF is image-only, use our OCR tool first to extract the text.

What is the similarity percentage?

The similarity percentage shows how much of the content is unchanged between the two documents. 100% means identical, while lower percentages indicate more differences.

Can I export the comparison results?

Yes, you can export the diff results as HTML for visual review or as plain text for processing in other tools.

Is there a file size limit?

Each PDF can be up to 20MB. For larger documents, consider splitting them first using our Split tool.

Is my file processed securely?

Your files are processed securely by the PDFSub Engine - an isolated server with no internet access. Files are encrypted during transfer and auto-deleted after processing.
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