Free Online PDF Metadata Editor

This application is a specialized utility for viewing and modifying document metadata in PDF files. It provides a secure, client-side interface to update essential PDF attributes like Title, Author, Subject, and Keywords without the need to upload sensitive documents to an external server.

Core Features

• Client-Side Processing: Uses the pdf-lib library to manipulate PDF bytes entirely in the browser memory.
• Drag-and-Drop Interface: Intuitive file upload area for quick PDF loading.
• Metadata Fields: Editable forms for Title, Author, Subject, Creator, Producer, and Keywords.
• Real-time Validation: Instant feedback on file validity and metadata extraction.
• Privacy First: Zero-server architecture ensures files never leave the user's local environment.
• Responsive Design: Works seamlessly on desktops and mobile devices.

UI Layout

• Header: Simple, descriptive heading and a brief sub-headline explaining the tool's privacy-focused approach.
• File Upload Area: A large, dashed-border dropzone area that changes state upon file detection.
• Editor Panel: A clean, card-based interface that appears only after a file is loaded. Includes input fields for all metadata types with clear labels.
• Action Bar: Prominent, high-contrast buttons for "Download Modified PDF" and "Clear/Reset" actions.
• No-Footer Policy: Strictly adheres to the requirement of having no footer branding.

Color Palette & Aesthetics

• Base: White (#FFFFFF) background with subtle off-white (#F9FAFB) sections for contrast.
• Primary: Professional Blue (#2563EB) for primary call-to-action buttons (Download).
• Text: Slate Gray (#334155) for headings and Dark Gray (#475569) for body text.
• Borders/Dividers: Soft gray (#E2E8F0) with rounded corners (border-radius: 8px) on all cards.
• Shadows: Soft, diffused shadows (box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1)) to provide a modern, "floating" card look.

Interactions & Animations

• Micro-interactions: Buttons will scale slightly (transform: scale(0.98)) on click and hover.
• Transitions: Smooth fade-ins (opacity: 0 to 1) for the editor panel when a file is successfully uploaded.
• Loading States: Simple CSS-spinner animations for when the PDF is being processed or generated.

Developer Directives

• Single File Constraint: All HTML, CSS (Tailwind CDN), and JavaScript (pdf-lib CDN) must reside in one single file.
• No Storage: Under no circumstances should localStorage or sessionStorage be used. Store the PDF Uint8Array in a JavaScript constant variable.
• Sandbox Compatibility: Do not use alert(), confirm(), or prompt(). Replace these with custom modal components (hidden divs that toggle display block/none).
• External Links: All links must have target="_blank" and rel="noopener noreferrer".
• Dependencies: Include pdf-lib via JSDelivr CDN. Use Tailwind CSS via CDN for styling to maintain a consistent SaaS aesthetic.