Compare PDFs
Side-by-side inspection of two documents. Analyzes page counts, dimensions, metadata, and performs word-level diff analysis with visual highlights.
Compare PDFs
Side-by-side inspection of two documents. Analyzes page counts, dimensions, metadata, and performs word-level diff analysis with visual highlights.
How to Use Compare PDFs
- Step 1: Upload Document A (Original)
- Step 2: Upload Document B (Modified)
- Step 3: Review diff summary and inspect changes
Technical Specifications & Limitations
- Maximum file size: 50 MB per document.
- Compares text tokens and document metadata; scanned image-only PDFs require OCR before diff comparison.
- Highlights added, removed, and modified words.
Troubleshooting Common Issues
⚠Compare says 'No text differences found' but visual layout differs.
The documents may contain identical text with different fonts or positions. Check the structural tab for dimension variations.
⚠Files are too large to process simultaneously.
Close background tabs to give the diff engine sufficient browser memory for token alignment.
🔒Privacy & Security Guarantee
All PDF processing for Compare PDFs occurs 100% inside your local web browser sandbox using WebAssembly and client-side JavaScript. Your documents, images, and data are never transmitted over the internet or saved to external servers. Full confidentiality is preserved for sensitive scientific research, financial records, and legal contracts.
Frequently Asked Questions
How does the text diff work?
SciHive extracts text tokens with coordinate references from both documents and runs a Longest Common Subsequence (LCS) diff algorithm.
Can I compare contracts or revisions?
Yes, it is designed specifically for legal contracts, drafts, and research paper revisions.
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