DualBook 8 languages

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Translate an English book into French

Upload an English EPUB and get the first fifteen pages back in French. Before the first sentence, two things have to be settled for the whole book: who says tu to whom, and what tense the narration lives in.

The first 15 pages of text are sent to our server to be translated. The file itself stays on your device.

The tu/vous problem is the obvious one. English "you" hides the relationship; French insists on it, in every verb, so each line of dialogue is also a claim about how close two people are. Decide that per paragraph and characters slide in and out of intimacy for no reason.

The tense question is less obvious and just as consequential. Literary French narration has a tense that spoken French does not use at all — the passé simple. Choosing it or refusing it sets the entire register of the book, and it has to be one choice, held from the first page to the last, not a coin flip per chapter.

Both are decided from the whole book. The model reads the complete text first and writes a guide — names, recurring terms, tone, narrative voice, who addresses whom how — and every page is then translated against that guide rather than against whatever came immediately before it.

How it works

  1. Choose your English EPUB

    A DRM-free EPUB. The file stays on your device; only the text of the sample is sent.

  2. The model reads the whole book

    Names, terms, register and the tu/vous map are settled once, from the complete text.

  3. The first 15 pages come back in French

    About 4,500 words, translated as continuous prose rather than sentence by sentence.

  4. Download, or read it here

    A complete EPUB. French punctuation conventions — guillemets, dashes for dialogue — are used, not English quotation marks.

What this free tool does not do

Fifteen pages, not the book. About 4,500 words, counted in words rather than chapters.

French runs longer than English, commonly 15–20%, so the sample covers fewer printed pages than the English it came from.

Typography is correct, not tuned. French wants a narrow non-breaking space before ; : ! and ?. The output uses a real non-breaking space, which every modern reader honours — older devices may set it a touch wide.

The text is sent to a server and discarded when the job finishes.

Questions

Does it use guillemets for dialogue?

Yes. French dialogue conventions are used — guillemets and dashes rather than English quotation marks — because a French book punctuated like an English one reads as a machine translation from the first page.

How is tu vs vous decided?

From the relationships mapped across the whole book, then held. This is the single clearest reason the model reads the entire text before translating: a paragraph on its own does not tell you whether these two people are colleagues or lovers.

Will the narration use the passé simple?

It follows the register of the original. A literary novel gets literary narration; a contemporary or first-person voice usually does not. What matters more than the choice is that it is one choice for the whole sample instead of drifting.

How much is free?

About 4,500 words, roughly fifteen pages, five books per day per person.

Translate the whole book

The app runs the same engine across the entire book and can show the French next to the English, with your position synced between devices.

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