LangBox: Bilingual Reading, YouTube Subtitles & Vocabulary Review

Translation under each paragraph, a double-click dictionary, and the words you look up return for review. Web, YouTube, PDF, EPUB.

Learn a language from what you already read and watch. LangBox puts a translation under every paragraph of the page you have open, gives you a dictionary on double-click, and brings back the words you looked up until you know them. The original text stays on the page; you understand first, then the new words stick. HOW IT WORKS Read. Click the LangBox icon on any page. Each paragraph gets its translation underneath, and the layout stays as it was. Auto-translate on the sites you choose. Look up. Double-click a word for pronunciation, part of speech, the meaning in your language, and a definition in the language you are learning. Remember. Words you looked up come back as short exercises in the sentence you found them in, spaced out with FSRS so you review just before you would forget. WHERE IT WORKS • Web pages: news, blogs, documentation, forums, any article in Chrome. • YouTube: dual subtitles, full transcript, dictation and shadowing practice from any video. • PDF: open a PDF and read the original beside the translation, with the same dictionary and review. • EPUB: read whole books chapter by chapter in two languages. • Academic pages such as arXiv and PubMed: prose is translated, formulas and citations are left untouched. NOTHING TO READ YET? LangBox comes with graded reading and practice: IELTS reading and listening, English from A1 to C2, workplace Japanese and Korean, Spanish from the first word. Everything you read in a course feeds the same review. PRACTICE FORMATS Fill in the blank, spelling, synonyms, sentence building, dictation, and feedback on IELTS-style writing. FREE, AND HONEST ABOUT IT • Free to install and to use as a guest, without an account. Sign in to sync across devices and get monthly LangBox model credits. • Bring your own key if you prefer: OpenAI, Anthropic or Gemini. Keys are stored on your device. • Translations are model output and can be wrong. They are a reading aid; check anything that matters. LANGUAGES Interface in English, Simplified and Traditional Chinese, Japanese, Korean and Spanish. Learn Spanish, Japanese, Korean, Chinese, English, French and more. Questions or feedback: https://langbox.site/en/contact/ Privacy: https://langbox.site/privacy/