Mentra – AI Reading Assistant for PDFs, Articles & YouTube

Chat with any page, PDF or YouTube video in a side panel. Summarize, ask questions, and save notes to Obsidian in one click.

Mentra is an AI reading assistant that lives in a Chrome side panel. Open it on any article, PDF, or YouTube video and get instant summaries, definitions, key terms, and answers to your questions — without copy-pasting into ChatGPT or leaving the page. Then save what matters straight to Obsidian. Built for students and researchers who read to learn and keep a second brain. WHAT YOU CAN DO • Summarize any web page, PDF, or YouTube video in seconds • Ask follow-up questions about what you're reading, in context • Extract key terms, simplify dense passages, get timestamped video summaries • Read PDFs (including arXiv papers) — parsed right in your browser • Save answers as notes, then send them to Obsidian in one click • Turn notes into flashcards and export them for spaced repetition STRAIGHT TO YOUR SECOND BRAIN Mentra doesn't lock your notes in. Export to Obsidian via a one-click link (clean Markdown with title, source, and tags) or download .md — works with Logseq, Notion, Anki, or plain files too. Mentra handles the capture; your vault handles storage and review. HOW IT WORKS 1. Click the Mentra icon to open the side panel. 2. Summarize or ask anything about the page, PDF, or video. 3. Use CTRL + Select text to deploy the tooltip and use the different features 4. Save it — and send it to Obsidian. PRIVACY PDFs are parsed in your browser; the file is never uploaded — only the text needed for your request is sent to generate the answer. Your notes live in your account and you can export or delete them anytime. PRICING Free with a generous daily limit. Upgrade to Pro for higher limits. No credit card to start. Great for: research papers, lecture notes, long articles, documentation, YouTube lectures, and anyone building a knowledge base in Obsidian.