Is Obsidian open source?
Last checked: 3 November 2026
A question a lot of people get wrong — because Obsidian feels open: your notes are plain Markdown files, and thousands of its plugins are open source. The app itself is a different story.
What is open, and what isn't
- Your notes: plain Markdown files in a folder you own. This part is genuinely open — your data is never locked in, which is exactly why leaving is possible at all.
- Community plugins: many are open source, published by their authors.
- The Obsidian app: proprietary and closed-source. So are its paid add-ons, Sync and Publish.
Does it matter?
For many people, no: the app is free, and your files are yours. It matters if you want to audit the code that handles your notes, guarantee the app can outlive its company, or modify the app itself. If any of those is a hard requirement, a closed-source app cannot meet it — no setting changes that.
What to use instead
Logseq, Joplin, SiYuan, AppFlowy, Zettlr and TriliumNext are genuinely open source (AGPL-3.0 or GPL-3.0); AFFiNE is open-core only. The full licence-by-licence breakdown is on the open source Obsidian alternatives page, and the picker quiz matches one of them to how you actually write.