Translate EPUBs
& PDFs with AI.
Drop in an EPUB or a PDF, get it back in your language — ready for any e-reader. Your text goes straight to the AI provider you choose, on your own API key. No account, no subscription.
Version 0.4.1 · macOS 12.3+ · Windows 10+ · Free
macOS is signed & notarized. Windows shows a SmartScreen warning — what to expect →
The Translate view — drop a book, choose a model, start translating.
57 languages
Albanian, Arabic, Belarusian, Bengali, Bosnian, Bulgarian, Catalan, Croatian, Czech, Danish, Dutch, English, Estonian, Filipino, Finnish, French, Galician, German, Greek, Hebrew, Hindi, Hungarian, Icelandic, Indonesian, Italian, Japanese, Korean, Latvian, Lithuanian, Macedonian, Malay, Malayalam, Mandarin (Simplified), Mandarin (Traditional), Marathi, Norwegian (Bokmål), Norwegian (Nynorsk), Persian, Polish, Portuguese (Brazil), Portuguese (Portugal), Romanian, Russian, Serbian (Cyrillic), Serbian (Latin), Slovak, Slovenian, Spanish, Swahili, Swedish, Tamil, Telugu, Thai, Turkish, Ukrainian, Urdu, Vietnamese
Libyx itself is translated into 56 languages — pick yours and the whole app follows, right-to-left scripts included.
Why Libyx
Built for readers, not subscribers
The only packaged desktop app that translates whole books on your own API key — with batch discounts, and without ever asking you to pay for the same chapter twice.
Never lose finished work
Cancel whenever you like. Finished chapters are already saved and are never re-run — you never pay for the same text twice.
Half price, overnight
Batch mode is a flat 50% off at Anthropic, OpenAI, Google and Mistral — on input, output and cached tokens alike. The app doesn’t even need to stay open.
Runs fully local, if you want
Point Libyx at Ollama or LM Studio on your own computer and the text never leaves your machine at all.
Built for consistency
A glossary and voice profile are built first and travel with every request, helping names, tone and invented terms stay consistent from the first chapter to the last.
You see the cost up front
An estimate before you start, the actual cost per chapter while it runs — in dollars, not credits.
A real app, not a script
Signed and notarized on macOS. No terminal, no Python environment, no account to create.
How it works
Drop your book
Drag and drop an EPUB or a PDF. A PDF is rebuilt into a real book first — and you can read the result and correct it before anything is paid for. Nothing leaves your computer except the text sent to your chosen AI model.
Choose a model
Claude, GPT, Gemini, Mistral, DeepSeek, or any OpenRouter model. Pick by quality and cost. Where the provider runs a batch queue, it delivers overnight at half price.
Get your translation
A complete EPUB you can read in your reader of choice. Optional polish pass for literary quality.
Under the hood
Details that matter
A PDF becomes a real book first
Libyx reads a PDF’s own typography — its columns, running heads and chapter openings — and rebuilds it as a proper EPUB before a word is translated. Proof & Fix then shows you what it made, so a stray heading or a paragraph broken in half is corrected before you pay for it.
Collect the web into one book
Paste a link or an article and it joins a pile. When the pile is ready, bind it into a single EPUB with a cover of its own — then translate it like any other book.
Several books at once
A running translation no longer holds the app hostage. Start one, go elsewhere, start another — each run keeps going in the background and says where it has got to.
Interrupted chapters rescue themselves
When a provider returns an incomplete chapter, Libyx re-fetches just the missing pieces instead of re-running the whole book.
Bilingual editions — even afterwards
Keep the original alongside the translation, in the order you choose. A book you’ve already translated can be rebuilt as a bilingual edition without a new run.
A verdict before you spend anything
Drop a book and Libyx maps its chapters, measures its length and estimates the cost — free, before an API key is even entered.
Translate exactly what you pick
Choose the chapters you want; copyright pages and other boilerplate are recognised and skipped automatically.
The book keeps its shape
Chapter structure, metadata and cover carry through — and right-to-left languages get their layout flipped automatically.
Bring your own API key
Libyx is not a subscription. You pay the AI provider directly. A typical book costs under $1 in batch mode, sometimes a few dollars for the highest-quality models.
Windows users — read this first
Windows Defender SmartScreen shows a warning the first time you run the installer. It’s expected and harmless — it appears because Libyx isn’t code-signed yet (Windows certificates are expensive and not yet in the budget), so Windows can’t recognise the publisher. To proceed:
- Click More info in the SmartScreen dialog.
- Click Run anyway.
- The app will open normally.
This warning returns with each new version and isn’t going away — Authenticode signing is a recurring annual cost that isn’t justified for a one-person project, so Libyx stays unsigned. It’s expected and doesn’t indicate anything wrong with the download. The guide has more detail.
macOS — signed & notarized
The macOS version is signed with a Developer ID certificate and notarized by Apple. Gatekeeper opens it without prompts on macOS 12.3+.
Actively maintained
What’s new
Version —
From the developer
Libyx is a one-person project. I’ve read a lot of books in English — but I always feel closer to a story in my native Swedish, so I built the tool I wanted and use it myself, continuously. There’s no company behind it, no investors, and no plan to bolt on a subscription. Your books and your keys stay on your machine.
If you run into a problem or have a suggestion, I’d genuinely like to hear it: [email protected].
Your next book, in your language.
Free to use — you only pay your AI provider, by the page.
Download Libyx