Bilingual Book Maker uses AI translation to produce bilingual editions of books and documents: give it an epub, txt, Markdown, SRT, or PDF file and it returns a version with the translation interleaved alongside the original text. The open-source project by yihong0618 has close to 10,000 stars on GitHub and remains actively maintained in 2026.
The tool was built for language learners and readers of foreign-language books who want to read the original with training wheels. It sends text to translation back ends — ChatGPT-style LLM APIs are the primary route, with support for several model providers and traditional translation services — paragraph by paragraph, then rebuilds the file with original and translation alternating so you can compare as you read. Options control chunk sizes, prompts, glossaries, and which parts of a book to translate, and a detailed wiki documents the measurements behind the defaults. It is deliberately a power-user tool: a single command can convert an entire novel overnight, and interrupted runs can resume instead of starting over — important when a full book means thousands of API calls.
Free. Bilingual Book Maker is open source under the MIT license. You supply your own translation API keys and pay only for the API usage you consume.
Language learners, bilingual readers, and translators who want side-by-side editions of books, manuals, or subtitle files — and readers tackling foreign-language literature with AI assistance.