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Opennote
ActiveThe notebook that thinks with you.
Summer 2025Founded 20253 peopleSan Francisco, CA, USA
About
Opennote is a notebook with an AI thinking partner built in. Feynman lives in your work: it edits your writing, references your knowledge and the web, runs background tasks, and gives feedback as you work.
Founders · 3
Launch
Launched on Y Combinator · Jul 2025
View launch post ↗Opennote is the interactive AI tutor that lives in your notes
Opennote embeds an AI tutor inside users’ notes, analyzing writing in real time to provide Socratic questions, targeted feedback, and visual explanations. It supports solo study and collaborative learning with real-time note sharing and publishing for a community of students, currently used by over 55,000 learners.
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