Onhand is a free, open-source Chrome extension designed to help students and researchers understand PDFs and webpages without constantly switching between tabs. Ask a question about the material you’re reading, and Onhand highlights relevant passages directly on the page, making it easier to verify answers against the original source. It can also follow citations to related research papers, while its Learning mode helps you study through guided questions and quizzes. Onhand offers a daily free tier with no sign-up required, and users can also connect their own ChatGPT plan or API key for additional flexibility.
