A premium, browser-based tool to optimize and repair EPUB files specifically for Amazon's "Send to Kindle" service. 100% client-side, offline-safe, and privacy-focused.
- Parallel Processing: Batch process multiple EPUBs simultaneously.
- Smart Repair:
- Fixes UTF-8 encoding declarations.
- Repairs broken NCX/Nav Table of Contents.
- Automatically handles malformed OPF structures.
- Sanitizes HTML and removes stray tags.
- Advanced Editing:
- In-browser Metadata Editor (Title, Author, Series, Language).
- Drag & Drop cover replacement.
- Visual Excellence:
- Optimized for 4K displays (responsive 2-column layout).
- Apple-inspired design with Dark/Light mode support.
- Real-time PT/EN localization.
- Privacy First: Files are NEVER uploaded to any server. Everything happens in your browser.
Due to security restrictions on ES6 modules and Service Workers, a local server is required.
Open your terminal in the project folder and run:
# Using Python (Pre-installed on most systems)
python -m http.server 8000Visit: http://localhost:8000
index.html: Main application entry point.styles.css: Advanced Apple-style design system.script.js: Application coordinator and state management.sw.js: Service worker for offline functionality.js/:epub-engine.js: Heart of the app. Handles EPUB reading, fixing, and writing.utils.js: Helper functions for compression and DOM manipulation.constants.js: Localization strings and configuration.
This app is a Progressive Web App. Once loaded via the local server for the first time, you can:
- "Install" it or "Add to Home Screen".
- Use it completely offline without needing to rerun the server command (provided the browser cache is maintained).
This application uses the zip.js library to deconstruct and rebuild EPUB files directly in your browser's memory.
- No files are uploaded.
- No analytics are tracked.
- No external APIs are called during processing.
Created with ❤️ for Kindle readers.