About PDF Compare Tool — Compare Two PDFs Side by Side Online
Upload two PDF files and instantly see a side-by-side diff highlighting what changed between them. Extracts all text from both documents via PDF.js, then runs an LCS-based diff algorithm. Switch between line-by-line, word-by-word, and character-by-character comparison modes. Added text is highlighted green, removed text is red, unchanged text is gray. See a similarity percentage score, plus counts of added/removed/unchanged blocks. Filter to show only changes. Export the diff as a text file.
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✨ Key Features of Our PDF Compare Tool — Compare Two PDFs Side by Side Online
- ✓LCS-based diff algorithm
- ✓Line, word & character modes
- ✓Color-coded diff view (green/red/gray)
- ✓Similarity score %
- ✓Filter changes only view
- ✓Export diff as .txt
📖 How to Use PDF Compare Tool — Compare Two PDFs Side by Side Online
1
Upload PDF A & B
Drop or select both PDF files.
2
Choose Mode
Select line, word, or character diff.
3
View Diff
See side-by-side colored diff view.
4
Export
Download the diff as a text file.
❓ Frequently Asked Questions
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