DualBook 8 languages

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Make a Japanese-Korean bilingual book

Each Japanese paragraph with its Korean translation directly beneath it, in one EPUB. The two sentences will line up almost clause for clause, which is what makes this pair worth reading in parallel.

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

Most bilingual reading asks you to hold two different sentence shapes in your head at once. Here you do not have to: Japanese and Korean build a sentence the same way, so the translation underneath usually runs in the same order as the original. You can follow it clause by clause and see exactly which particle became which particle, which verb ending became which.

That makes the parallel form unusually efficient for a Korean reader learning Japanese. The structure is already familiar; what has to be learned is the vocabulary and the script, and both are easier to absorb when the grammar around them is not also new.

Your browser opens the EPUB, walks each paragraph and inserts the Korean beneath it inside the original file, rewriting only the chapter documents that received a translation.

How it works

  1. Choose a Japanese EPUB

    A DRM-free EPUB. The bilingual file is assembled in your browser, not on a server.

  2. The model reads the whole book

    The cast and their relationships are mapped once, so the Korean speech levels stay consistent throughout.

  3. Korean is inserted under each paragraph

    Each translation is styled beneath its paragraph — and because Hangul and kanji look nothing alike, the two blocks are easy to tell apart at a glance.

  4. Read it here, or on your phone

    A complete EPUB carrying the book's own fonts and stylesheets, writing mode included.

The trap, and the honest limits

Your eye will go to the Korean. Read the Japanese paragraph first, every time. With this pair the temptation is strong precisely because the Korean maps so neatly onto what you were about to work out.

No furigana is added. Ruby has to be authored, not generated, so a kanji compound you cannot read stays unread — which is what the translation underneath is for.

Fifteen pages get translations. The rest of the book stays in Japanese inside the same file.

The text is sent to a server and discarded when the job ends. The file never leaves your device.

Questions

Which side should I read first?

Japanese first, every paragraph. Give yourself the few seconds of working it out before you look down.

Why is this pair good for parallel reading?

Because the sentence structures match. The translation underneath usually runs in the same clause order as the original, so you can compare piece by piece — which is rarely possible between languages that build sentences differently.

Is furigana added?

No. Ruby is authored into a book rather than generated afterwards, and guessing readings, especially for names, is usually wrong.

Does the vertical layout survive?

Yes. The file keeps its own stylesheet including its writing mode, and the Korean is inserted as an ordinary paragraph following whatever the book already does.

The whole book, in parallel

The app builds the bilingual version of the entire book, with tap-to-look-up and your reading position synced across devices.

Open DualBook