Language Reactor

Language Reactor is a language learning toolbox that works on top of native media, most notably Netflix and YouTube, so learners can study a new language by watching content they already enjoy. The core problem it addresses is that ordinary streaming players offer little support for language study: subtitles cannot be shown in two languages at once, unknown words require switching to a separate dictionary, and there is no built-in way to review what was learned.

Language Reactor solves this by adding an interactive layer to the video player. It displays dual subtitles, lets users click words or phrases to look them up, pause automatically after each line, and save items for later review. The project was formerly known under a different name (Language Learning with Netflix) before it became Language Reactor. It runs as a browser extension and positions itself as a general toolbox for discovering, understanding, and learning from native materials.