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Each English paragraph with the Japanese directly underneath, in one EPUB. Read the English first and look down only when you have to — the order is what makes it practice rather than reading a translation.
The first 15 pages of text are sent to our server to be translated. The file itself stays on your device.
Parallel text suits Japanese learners of English particularly well, because the two languages disagree about word order so completely that a dictionary rarely resolves a sentence. Knowing every word and still not knowing what the sentence says is the normal experience, and a translation underneath answers it instantly.
Your browser opens the EPUB, finds each paragraph and inserts the Japanese beneath it, inside the original file. Chapters, table of contents and cover survive untouched.
The layout is stacked. That is not only an EPUB constraint but a Japanese one: a vertically-set book and a side-by-side column layout cannot both be true, and the stacked form works in either writing mode.
A DRM-free EPUB. The bilingual file is built in your browser, not on a server.
Each character's speech level is decided once from the whole book, so the Japanese does not lurch between registers.
Each paragraph gets its translation styled beneath it, so the two are easy to tell apart.
The file keeps its own fonts and stylesheets, including writing mode.
Your eye will jump to the Japanese. Read the English paragraph first, every time, and sit with the confusion for a moment. That moment is the practice.
No furigana is added to the Japanese — ruby has to be authored, not generated.
Fifteen pages get translations. The rest stays in English in the same file.
The text is sent to a server and discarded when the job ends.
English first, always. Reading the Japanese first means you can finish an entire book having practised almost nothing.
No. Ruby is something an author writes into a book, not something generated after the fact, so adding it would mean guessing readings — including for names, where guessing is usually wrong.
Yes. Kindle has accepted EPUB directly since 2022; email it to your device or copy it across.
Yes. The browser rebuilds the archive entry by entry and only changes the chapter files that received a translation, so cover, navigation and metadata pass through untouched.
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The app builds the bilingual version of the entire book, with tap-to-look-up, readings and pronunciation, and your position synced across devices.
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