Sublern is an AI tool that translates words in video subtitles in real time and generates missing subtitles via speech recognition or OCR. Hover over a word to see translation, examples, and hear pronunciation — all without pausing the video. Save words and practice with SRS flashcards or the Scramble game. Supports multiple languages, works on any video site, and offers customizable shortcuts. No slowdown, no tab switching. Learn languages naturally while watching videos.