Translate an EPUB
Translate a whole EPUB into another language with your own API key — Claude, GPT, Gemini or any OpenAI-compatible endpoint. The book is rebuilt in your browser.
How it works
Drop an .epub and it is opened here in the page: the spine is read, each chapter is scanned, and the runs of text between the markup are collected in reading order. You pick a provider — Anthropic, OpenAI, Google, or any OpenAI-compatible endpoint you type in yourself — paste your own key, choose a language, and the passages are sent a few at a time. When the last one comes back the book is rebuilt and downloaded — same chapters, same images, same stylesheets, translated text.
Where your text goes — read this one
Every other tool on this site keeps your file in the tab. This one cannot: translation needs a model. The text goes from your browser straight to whichever provider you picked, under your key, and the result comes straight back. It does not pass through ketchio, because ketchio has no server for it to pass through. Your key is sent to that provider and nowhere else, and it is only stored in this browser if you tick the box. If the manuscript is confidential, that decision is between you and them — read the terms of whoever you send it to, not ours. A local endpoint, such as Ollama or LM Studio on your own machine, keeps even that inside your network.
What is translated and what is not
The text you read: paragraphs, headings, captions, list items, chapter titles. Left exactly as they were: markup, class names, stylesheets, images, fonts, link targets, page-break structure, image alt text, and the book’s own title and author in the package metadata — so it stays findable in your library. Code inside script and style elements is never sent. The package language and each chapter’s own language attribute are updated together, so readers pick the right hyphenation and font. Segments with no letters in them — a stray number, a dash — are skipped rather than burned on a round trip.
Cost, limits and honesty
You pay your provider directly; we take nothing, because there is nothing for us to take. Where we know a model’s published price we show the cost; where we do not, we show the token count and leave the arithmetic to you rather than guess. An estimate is shown before you start and the real token count and cost when it ends. A long novel is a real expense — check the estimate. Machine translation of a book is a draft, not a finished edition: it will not carry a translator’s judgement about rhythm, register or a pun, and you should read it before you publish it. The rebuilt file is written to EPUB spec, mimetype first and uncompressed, so it opens in normal readers — the EPUB Validator on this site will tell you if anything is off.