# PDFCheck - PDF Metadata Analyzer & Validator > Free online PDF analysis tool. Check metadata, validate documents, detect AI-generated PDFs, and optimize file size. 50 free checks daily with account. PDFCheck is a comprehensive PDF analysis platform that helps verify document authenticity, extract metadata, detect AI-generated content, and optimize PDF files. ## Main Tools - [PDF Metadata Checker](https://pdfcheck.io/) - Analyze PDF creation date, author, software, and edit history - [PDF Validator](https://pdfcheck.io/pdf-validator) - Validate PDF structure and check for corruption - [AI Detection](https://pdfcheck.io/pdf-ai-detection) - Detect AI-generated PDF signatures (ChatGPT, Claude, etc.) - [PDF Optimizer](https://pdfcheck.io/optimize-pdf) - Compress and reduce PDF file size - [PDF Signature Checker](https://pdfcheck.io/pdf-signature-checker) - Verify digital signatures and certificates in PDFs - [PDF Image Extractor](https://pdfcheck.io/extract-images) - Extract all images from PDF documents with original quality - [PDF Accessibility Checker](https://pdfcheck.io/pdf-accessibility-checker) - Check PDF accessibility compliance, tagged structure, and WCAG readiness ## Resources - [How It Works](https://pdfcheck.io/how-it-works) - PDF analysis methodology - [API Documentation](https://pdfcheck.io/api-docs) - REST API for developers - [MCP Server](https://pdfcheck.io/mcp-server) - Model Context Protocol server for AI integrations - [Tools Directory](https://pdfcheck.io/pdf-tools) - Database of PDF software signatures - [Sitemap](https://pdfcheck.io/sitemap) - All pages and resources ## API Access Registered users get 50 free PDF analyses per day. API endpoints available: - `POST /api/v1/pdf/analyze` - Upload and analyze PDF - `GET /api/v1/pdf/{id}` - Retrieve analysis results - `GET /api/v1/user` - Check usage and remaining quota ## More Information - [Full Documentation](https://pdfcheck.io/llms-full.txt) - Detailed technical documentation - [About](https://pdfcheck.io/about) - Our mission - [Privacy Policy](https://pdfcheck.io/privacy) - Data handling practices