Obsidian
publishedLocal-first knowledge base with markdown files
A knowledge management tool that stores notes as plain markdown files on your local filesystem. No lock-in by design: your notes are yours, stored in folders you control. Plugins extend functionality. Optional paid sync service.
Trust Surface
Interoperability
Business Model
Quick Facts
| RSS | Not available |
| Federation | no |
| API | Available |
| Chronological Feed | na |
| Algorithmic Feed | na |
| Deletion | yes |
| Open Source | partial |
| Moderation Transparency | partial |
Why It Belongs
Why It Belongs Here
Obsidian takes the strongest possible stance on data ownership: your notes are plain markdown files in a folder on your computer. No proprietary database, no cloud lock-in, no format conversion needed.
The app is free for personal use. Paid features (sync, publish) are optional add-ons, not requirements. The plugin ecosystem is community-driven and extensive.
Tradeoffs
Tradeoffs
- Not fully open source: The core app is proprietary (free but closed source). Only plugins are open
- Sync costs money: The built-in sync is $4/month. Alternatives (iCloud, Syncthing) work but with friction
- No real-time collaboration: Single-user editing only
- Plugin security: Community plugins can access local files — requires trust
- Mobile experience: The mobile app is functional but less polished than desktop
Claims (4)
Notes are plain markdown files — zero vendor lock-in for data.
The core application is proprietary despite the "local-first" philosophy.
Community plugins have full filesystem access, creating a trust surface.
No account required for full functionality — sync and publish are optional paid add-ons.
Evidence (4)
Obsidian official: plain markdown files in local folders, no sign-up required
strongOfficial pricing page: "Free without limits. No sign-up required. No strings attached." Security page: "Your data is saved locally on your device. No account is required." Vault is a folder of .md files + hidden .obsidian config directory.
Obsidian license: proprietary, free for all use (commercial license optional since Feb 2025)
strongObsidian is proprietary software. As of February 2025, commercial license became optional — anyone can use for work, free. Analysis: "being free to use does not make a piece of software open-source by default." Core Electron app is closed source; plugin API and ecosystem are open.
Obsidian plugin security: "cannot reliably restrict plugins" — official docs
strongOfficial: "Due to technical limitations, Obsidian cannot reliably restrict plugins to specific permissions or access levels." Lead developer confirmed on forum: "there is ABSOLUTELY NO SECURE WAY to run plugins without severely crippling the plugin API." Plugins can access NodeJS child_process. Standard Notes comparison: plugins run as first-party code with full filesystem access.
Obsidian ecosystem: 2,744 plugins, 1.5M MAU, two Cure53 security audits
strong2,744 community plugins, 416 themes. 1.5M+ monthly active users with 22% YoY growth. 5M+ total downloads. Two Cure53 penetration test audits (Dec 2023, Dec 2024). AES-256 encryption for Sync. No telemetry on desktop/mobile.