Compare PDF
Inspect textual and structural differences between two PDF documents side by side.
Client-Side Document Comparison
Compares page counts, extracted word vocabularies, and textual differences between two PDF files locally in your browser. Both documents remain strictly on your device.
Select first PDF
Select second PDF
How to Use Compare PDF
Select Document A
Choose your original PDF.
Select Document B
Choose the revised or modified PDF.
Compare
View similarity scores and page-by-page differences.
Key Capabilities
Local Execution
Extracts coordinate-level text and vocabulary from both documents using client-side Web Workers, computes set differences and token frequencies, and generates a structured diff report.
- •Works best for comparing text revisions, contracts, and essay drafts.
- •Heavily formatted documents with shifting paragraphs may show lower token alignment scores.
Visual & Structural Document Comparison
High-Resolution Visual Diffing
Both PDF documents are rendered synchronously into memory canvases at identical DPI settings. Pixel-level difference algorithms highlight layout shifts, modified numbers, and text additions.
Synchronized Navigation
Page flipping and scroll actions are locked between the two documents, allowing instant visual spot-checking of complex legal contracts and engineering blueprints.
Structural Integrity
Neither document is modified during comparison. You can inspect differences between revisions with complete confidentiality.
- •Best suited for comparing revisions of the same contract, specification, or presentation.
- •Documents with differing page counts can be aligned by navigating individual pages.
- •Comparison rendering runs locally without document transmission.
Frequently Asked Questions
Does this perform legal redline certification?↓
No. PDFSimplify provides algorithmic text and word-frequency comparison for convenience and revision tracking, not statutory legal redline verification.
Are either of my files uploaded?↓
No. Both documents are processed exclusively in your device browser RAM.
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