Obsidian
Dynalist Inc.
Obsidian is the leading personal knowledge management (PKM) tool, built around the principle that your notes belong to you. All data is stored as plain markdown files on your local device — no cloud lock-in, no proprietary format. Features bidirectional linking (wiki-style [[note]] references), a visual knowledge graph, a canvas for spatial note layouts, and 4,300+ community plugins that extend it to cover AI chat (Smart Second Brain), spaced repetition, task management, publishing, and more. Free for personal use forever. Commercial license: $50/user/year. Sync add-on: $5/month. Best for researchers, writers, and knowledge workers building a long-term second brain.
Free: personal use forever (all core features). Catalyst supporter: $25 one-time. Sync: $5/mo. Publish: $10/mo. Commercial license: $50/user/year.
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