Last updated: 2026-10-08
There is no single best EPUB translator. There is a best one for your situation: whether you want to pay nothing and are happy to configure software, whether you need formats other than EPUB, or whether you just want one finished book back without setting anything up. This page compares the seven options that come up most often, including the ones that beat us.
We make EPUB Translator, so read this with that in mind. Every competitor fact below was checked against that product's own website or GitHub repository on 2026-10-08, and links to the source. Anything we could not confirm there is left out. Prices change — follow the links before you buy.
| Option | Cost model | EPUB in → EPUB out | Setup | Bilingual output |
|---|---|---|---|---|
| Calibre + Ebook Translator | Free; paid engines use your key | Yes | Desktop app + plugin | Yes |
| BookTranslator.app | Pay per task or credit packs | Yes | Web app | Yes |
| BookTranslator.ai | Pay per book (per 100k words) | Yes (EPUB only) | Web app | Not stated |
| Immersive Translate | Free plan + subscriptions | Yes | Browser extension / app | Yes |
| DeepL | Free plan + subscriptions | No EPUB support | Web / desktop app | No |
| ChatGPT / Claude | Chat subscription | No, text back | None | Only if you ask |
| EPUB Translator | Pay once per book, no plan | Yes | Web app, sign in | Yes, both files |
The most-recommended free option, and for good reason. Calibre is a free, open-source (GPL-3.0) e-book manager for Windows, macOS and Linux, and the Ebook Translator plugin (also GPL-3.0, latest release v2.4.2 on 2026-08-07) adds translation to it.
Where it is weaker: you install a desktop app, add a plugin, pick an engine, get an API key if you want an LLM, and tune settings. The free engines are classic machine translation rather than a large language model, which in our experience shows most on dialogue-heavy fiction. Full comparison: EPUB Translator vs Calibre Ebook Translator.
Two different companies share this name. BookTranslator.app (run by Lovin, LLC) is the one most lists mean:
BookTranslator.ai is a separate, EPUB-only service: $6.99 per 100,000 words on Basic, $9.99 on Pro, with a $6.99 minimum and a 7-day money-back guarantee.
Full comparison: EPUB Translator vs BookTranslator.
A subscription translation suite whose core is a browser extension for bilingual reading on any web page; e-books are one of many surfaces.
Best if you read foreign-language content every day, not just one book. See EPUB Translator vs Immersive Translate.
DeepL is excellent sentence-by-sentence machine translation, and it shows up in every "best translator" list. But DeepL's document translation format list covers DOCX, PDF, HTML, TXT and many others — not EPUB. To use it on a book you would convert the EPUB to another format and rebuild it afterwards, or reach it through the Calibre plugin above. Its Individual plan (shown as €7.49/month billed annually in our region) includes 3 file translations a month.
General chat assistants translate well, and Claude even accepts an EPUB upload (up to 500 MB per file). What comes back is chat text, not a rebuilt book: on a whole novel you work through usage limits chapter by chapter, keep names consistent by hand, and reassemble the EPUB yourself. A Claude Pro plan is $20 billed monthly. For a chapter this is the quickest route; for a book it becomes a project. More in translating a book with a chat model yourself.
If you are comfortable on the command line, bilingual_book_maker and oomol-lab/epub-translator are MIT-licensed tools that turn an EPUB into a bilingual EPUB with a large language model. Both are free and both need your own API key.
A web app built for one job: upload an EPUB (or a text-based PDF), get back a complete translated EPUB with chapters, images, footnotes and the table of contents intact.
Through 2026-10-31 (UTC) every per-character rate is half price; the regular rate is $0.008–$0.025 per 1,000 characters, and the $3.99 minimum is not discounted.
Where we are weaker: far fewer target languages than Immersive Translate or BookTranslator.app; EPUB and text PDFs only (no MOBI, DOCX or scans); no paragraph-by-paragraph editor like the Calibre plugin's Advanced Mode; you need an account; and it is not free. If you want the absolute cheapest route, see the cheapest way to translate a book.
It depends on the job. Calibre with the free Ebook Translator plugin is the best free option if you are willing to install and configure it. BookTranslator.app covers the most formats and languages. Immersive Translate is best for daily bilingual reading. EPUB Translator is the simplest way to turn one EPUB into a finished translated EPUB, paying once per book.
Yes. Calibre with the Ebook Translator plugin is free and open source, and its free engines (Google, DeepL Free, Microsoft Edge) need no API key. Immersive Translate also has a free plan that includes bilingual e-books. Paid LLM engines inside these tools still bill you through your own API key.
Not directly. EPUB is not in DeepL's list of supported document formats, so you would need to convert the book to another format first or use DeepL as an engine inside the Calibre Ebook Translator plugin.
Calibre's Ebook Translator plugin, BookTranslator.app, Immersive Translate, the open-source bilingual_book_maker and EPUB Translator all produce a bilingual EPUB with the original and the translation together.
From nothing (Calibre with a free engine) to a few dollars to a subscription. With EPUB Translator a typical 500,000-character novel costs about $4.75, paid once. A worked comparison for a 400-page book is on the cheapest way to translate a book.