Obsidian
Free (personal) / Sync ~$4 per mo
OneNote
Free (with a Microsoft account)
Obsidian is a local-first, plain-text knowledge base with linking and plugins that you fully own. OneNote is Microsoft's free, flexible notebook with a freeform canvas and tight Microsoft 365 integration. Obsidian wins on privacy, ownership, and linked notes; OneNote wins on freeform flexibility and being free.
Pick Obsidian if you want a private, local-first notes vault you fully own, with deep linking, a graph view, and plugins.
Pick OneNote if you want a free, flexible freeform notebook with ink and media anywhere, especially within Microsoft 365.
Obsidian and OneNote are both beloved note apps, but they sit on opposite sides of a philosophical line. Obsidian stores plain-text Markdown files on your own device, so your notes are private, work offline, and remain readable even if the app disappears, with deep linking, a graph view, and a huge plugin ecosystem for power users. OneNote is Microsoft's free notebook, built around a flexible freeform canvas where you can place text, images, and ink anywhere, with tight Microsoft 365 integration.
On price, Obsidian is free for personal use (with paid add-ons like Sync around $4 a month), and OneNote is free with a Microsoft account. The choice is mostly privacy, ownership, and linked notes (Obsidian) versus a free, flexible freeform notebook (OneNote).
We compare privacy, structure, freeform notes, plugins, and price.
| Quick facts | Obsidian | OneNote |
|---|---|---|
| Where notes live | Your device (local files) | Microsoft cloud |
| Price | Free / Sync ~$4/mo | Free (Microsoft account) |
| Linked notes / graph | Best-in-class | Limited |
| Freeform canvas | Limited | Best-in-class |
| Best for | Privacy + linked notes | Free + flexible notebook |
Each row reflects the feature on each product's current public release.
| Feature | O Obsidian | O OneNote |
|---|---|---|
| Local-first / offline | Best-in-class | Limited |
| Plain-text ownership | Yes | No |
| Linked notes / graph view | Best-in-class | Limited |
| Freeform / canvas notes | Limited | Best-in-class |
| Plugin ecosystem | Huge | Limited |
| Microsoft 365 integration | No | Native |
| Fully free | Personal use | Yes |
| Privacy (data on your device) | Yes | No |
Pricing and features change often. Always verify the current details on each product's official site. Last reviewed June 2026.
Things neither product's marketing page leads with.
Obsidian gives you privacy, ownership, and powerful linking, but has a learning curve and stores notes locally by default.
OneNote is free and flexible with a freeform canvas, but it lives in Microsoft's cloud and lacks Obsidian's linking and plugins.
For a private knowledge base Obsidian leads; for a free, casual notebook OneNote is hard to beat.
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