PDF Change Analyzer - PDF Compare & Diff

Compare two PDFs locally. Find text, visual, number & date changes without uploading files.

Compare two PDF versions side-by-side with zero cloud uploads. Detect visual edits, modified sentences, and critical numerical shifts instantly. Whether reviewing contracts, invoices, agreements, or technical specs, PDF Change Analyzer highlights exactly what changed between two versions with 100% local in-browser processing. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 3-LAYER DOCUMENT ANALYSIS ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 1. CRITICAL NUMBER & DATE SHIFT ALERTS - Automatically detects and flags changes in pricing, payment terms, deadlines, and percentages (e.g., "$5,000 → $6,500" or "30 days → 15 days"). - Highlights modified invoice totals and contractual figures before signing. 2. DETAILED TEXT DIFF - Line-by-line sentence additions (+) and deletions (-) mapped with exact page references. - Displays side-by-side word changes without losing layout context. 3. VISUAL CANVAS DIFFERENCE LAYER - Pixel-level canvas comparison highlights relocated paragraphs, altered formatting, or inserted signatures in high-contrast red. - Catches visual formatting changes that text-only tools miss. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ PRIVACY & SECURITY ARCHITECTURE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ - 100% Local In-Browser Processing: Your PDF files are processed directly inside your browser memory and are NEVER uploaded to any remote server. - Zero Website Host Permissions: Does NOT read your browsing history, open tabs, or web page contents. - Zero Third-Party Telemetry: No remote tracking, analytics, or external server calls. - Optional On-Device AI: Leverages Chrome Built-in AI (Prompt API) when available, with a full deterministic fallback when unavailable. No PDF data is sent to cloud AI servers. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ IDEAL FOR ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ - Reviewing updated contracts, NDAs, and service agreements - Spotting modified totals, bank details, or terms on revised invoices - Auditing multi-page reports and technical specification revisions - Academic research and draft version comparisons ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ HOW TO USE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 1. Click the extension icon. 2. Select Version A (Original) and Version B (Revised). 3. Click "Compare PDF Versions". 4. Review highlighted number shifts, text diffs, and visual canvas overlays. 5. Export the structured summary report with one click.