Turn your EPUBs into audiobooks with neural text-to-speech — entirely in your browser.
EPUB Player is a free, open-source Progressive Web App (PWA) that transforms your EPUB ebooks into audiobooks using AI-powered text-to-speech. Everything runs locally in your browser — your books never leave your device.
No accounts. No uploads. No subscriptions. Just your books, as audio.
| Principle | What it means |
|---|---|
| Local-first | Your books, audio, and settings live in your browser's storage. Nothing is ever sent to a server. |
| Mobile-first | Designed for phones first, with responsive layouts for tablets and desktops. |
| Offline-capable | After the first load, the app works without internet. Listen anywhere. |
| Privacy by default | No accounts, no tracking, no analytics. Your reading habits are yours alone. |
- 📚 Import any EPUB — drag and drop or select files
- 🎙️ Neural TTS — natural-sounding voices via Kokoro (WebGPU/WASM)
- 🔒 100% local — your books never leave your device
- 📱 Works everywhere — phone, tablet, desktop
✈️ Offline support — listen anywhere after first load- ⏱️ Full audiobook controls — bookmarks, speed control, sleep timer
- 🎨 Lock screen controls — Media Session API integration
- 💾 Audio caching — generated audio is saved for instant replay
| Engine | Quality | Speed | Requirements |
|---|---|---|---|
| Kokoro | ★★★★★ | Moderate | WebGPU (best) or WASM fallback |
| Supertonic | ★★★★☆ | Fast | WebGPU |
| Piper | ★★★☆☆ | Fast | WASM |
| Browser TTS | ★★☆☆☆ | Instant | Built-in (varies by device) |
→ Try EPUB Player — it's live and free!
Or run it locally:
# Clone the repository
git clone https://github.com/grworg/epubplayer.git
cd epubplayer
# Install dependencies
npm install
# Start development server
npm run devOpen http://localhost:5173 in your browser.
- Node.js 18+
- npm 9+
npm run dev # Start dev server
npm run dev:host # Start dev server accessible on LAN (for phone testing)
npm run build # Production build
npm run preview # Preview production build
npm run typecheck # TypeScript check
npm run lint # ESLint
npm run format # Prettier
npm run test # Run unit tests
npm run test:e2e # Run Playwright e2e tests
# SEO
SITE_URL=https://epubplayer.com npm run seo:sitemap # Generate sitemap.xmlFor the best mobile debugging experience with WebGPU:
- Connect your phone via USB
- Enable USB debugging on the phone
- Open
chrome://inspect/#deviceson desktop Chrome - Enable port forwarding:
localhost:5173→127.0.0.1:5173 - Open
http://localhost:5173on your phone
This keeps the origin as localhost, which is required for WebGPU to work.
EPUB Player is built with:
- React 19 + TypeScript
- Vite (with PWA plugin)
- Tailwind CSS v4
- Zustand (state management)
- Dexie (IndexedDB wrapper)
- Web Workers (TTS generation off main thread)
src/
├── app/ # App shell, routing
├── features/ # Feature modules
│ ├── library/ # Book library & import
│ ├── player/ # Playback, buffering, audio backends
│ ├── settings/ # User preferences
│ └── ...
├── services/
│ ├── storage/ # IndexedDB repositories
│ ├── tts/ # TTS engines, workers
│ └── epub/ # EPUB parsing
└── ui/ # Shared components, icons
For detailed architecture documentation, see docs/architecture.md.
For the reasoning behind design decisions, see the Architecture Decision Records.
Contributions are welcome! Please read our Contributing Guide before submitting a PR.
- Fork the repository
- Create a feature branch:
git checkout -b feature/amazing-thing - Make your changes
- Run checks:
npm run typecheck && npm run lint - Commit with a clear message
- Push and open a Pull Request
EPUB Player is designed with privacy as a core principle:
- No accounts — nothing to sign up for
- No server — the app is purely client-side
- No uploads — your books stay on your device
- No analytics — we don't track you
- No ads — ever
Your data is stored in your browser's IndexedDB and never transmitted anywhere.
EPUB Player is free and always will be. If you find it useful and want to support development:
No pressure — using and sharing the app is support enough!
MIT — see LICENSE for details.
- Kokoro TTS — Neural text-to-speech model
- epub.js — EPUB parsing
- Dexie.js — IndexedDB wrapper
Made with ❤️ for audiobook lovers everywhere