4 U By U — Lecture to Study Notes

Turn the YouTube lecture you are watching into topic-wise study notes. Your own API key, one HTML file. No account, no server.

4 U By U turns the YouTube lecture you are already watching into study notes you can keep. Open a lecture, press the button in the corner, press Generate, and a few minutes later you have one HTML page: chapters divided by topic rather than by equal slices of the clock, timestamps that open the lecture at the right minute, plain-English explanations, a mental model for each idea, the key points, the mistakes to avoid, and a short check-yourself list. Keep it, search it, or print it. WHAT MAKES IT DIFFERENT - It reads the lecture you are already on. Nothing to upload, no link to paste, no second app. - Chapters follow the ideas, not the clock. The timestamps take you back to the moment; they do not split the page. - It does not invent what it could not read. If a stretch of the lecture cannot be written up, the page says so in words, with the provider's own reason and that stretch's own words underneath. A heading that looks real but was made up would be worse than a gap. - It shows the cost before it spends it: how many calls, roughly how many tokens, and how many lectures of this size the model's free day still holds. - Nothing is spent twice. Each finished part is kept on your machine, so a closed tab, a rate limit or a dead battery costs you the wait and not the work. WHAT YOU NEED A free API key from Groq (console.groq.com/keys). You paste it once and it stays in your browser. The notes are written with your key and your quota; there is no account with us, no subscription, and no server of ours in the middle. The estimate is shown before the first call. On the default model a one-hour lecture is roughly 42,000 tokens, about four lectures a day on the free tier. PRIVACY No account, no analytics, no advertising, no tracking, and no server of ours. The extension does not download or run code from the internet. The only request that leaves your browser goes to the AI provider you configured, with your own key, and only when you press Generate. The page you download opens offline and calls nothing. HONEST LIMITS - English captions only, for now. The notes are written in English from English captions; a lecture in another script is refused before anything is spent, and the panel says exactly why. - Free tiers meter tokens per minute, so a long lecture waits between calls instead of failing. Longer lectures take proportionally longer, and the panel shows the wait. - The notes are written by an AI model. They are a study aid, not a substitute for the lecture, and the lecture's own words are quoted on the page so you can check them. MIT licensed and developed in the open: https://github.com/anikethana21/4ubyu