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⚖️ 100% In-Browser Diff • Visual • Text • Structural • Zero Server Uploads

Compare PDFs (Side-by-Side Diff)

Compare two PDF documents side-by-side with synchronized scrolling, visual swipe comparison, pixel difference overlays, text modification tracking, and structural metadata inspection.

Document A (Baseline / Original) PDF format

Drop Document A here

or click to browse

Document B (Modified / New Version) PDF format

Drop Document B here

or click to browse

How In-Browser Multi-Dimensional PDF Comparison Works

Traditional PDF comparison tools rely on uploading your sensitive legal contracts, blueprints, or financial reports to third-party cloud servers. IMGFixy executes 100% of the comparison algorithms directly inside your web browser using WebAssembly and client-side rendering engines.

📝

Token-Level Myers Diff

Extracts every word token, computes Longest Common Subsequences (LCS), and precisely highlights added, removed, or rewritten sentences.

🎨

Pixel Diff & Swipe

Renders vector graphics and images to high-DPI canvases, performing pixel-by-pixel comparisons with heatmaps and interactive split-sliders.

📐

Structure & Metadata

Inspects PDF object dictionaries, embedded fonts, form fields, hyperlinks, document dimensions, and creation timestamps.

Frequently Asked Questions About PDF Comparison

Are my documents uploaded to any remote server? ▼

No. IMGFixy utilizes client-side WebAssembly, PDF.js, and PDF-Lib. Both Document A and Document B remain strictly inside your browser's sandboxed local memory. Zero bytes leave your machine.

What happens if pages were inserted, deleted, or reordered? ▼

Our Intelligent Page Matching algorithm computes a similarity matrix across all pages using Sørensen-Dice text similarity and page aspect ratios. It accurately maps inserted or deleted pages without falsely offsetting subsequent pages.

What is the difference between Side-by-Side and Swipe Slider modes? ▼

Side-by-Side mode presents two synchronized viewports with proportional scrolling for reading line-by-line differences. The Swipe Slider overlays both pages in a single viewport with a draggable divider bar to spot subtle typographic and graphical shifts.

Can I compare scanned PDF documents or image-only PDFs? ▼

Yes! Visual Pixel Diff, Swipe Slider, and Blink modes compare the rendered graphical bitmaps directly, highlighting visual changes even if the PDF contains no extractable text layer.

Can I export a technical audit comparison report? ▼

Yes. You can export a comprehensive human-readable Text Report (.txt) or a machine-readable structured JSON Audit (.json) detailing all modified pages, text snippets, and structural properties.

Does the tool modify either of my original PDF files? ▼

No. The comparator engine treats both files as strictly read-only. All diff markers, bounding boxes, and canvas overlays are generated in transient memory.

How are interactive form fields and annotations compared? ▼

Our engine inspects the underlying AcroForm dictionary and page annotation arrays, detecting added, deleted, or renamed form controls, signatures, text highlights, and hyperlinks.

What keyboard shortcuts are available? ▼

You can use J or → to jump to the next difference, K or ← for the previous difference, S for Swipe Mode, and D for Side-by-Side Mode.

Can I compare PDF files on mobile or tablet devices? ▼

Yes. The UI automatically adapts to touch screens and smaller viewports, allowing you to swipe between documents, toggle views, and inspect differences smoothly.

Is there any limit on document size or page count? ▼

Since all processing happens in your device's memory, the comparator easily handles documents up to several hundred pages depending on available system RAM.

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