Is Obsidian Open Source? What You Actually Need to Know About Its License and Code

Obsidian has become one of the most talked-about note-taking apps in the productivity space, attracting developers, writers, researchers, and knowledge workers who want more control over how they manage information. One of the first questions people ask before committing to any tool is whether it's open source — and with Obsidian, the answer is more nuanced than a simple yes or no.

Obsidian Is Not Open Source

Let's be direct: Obsidian is not open source software. Its core application code is proprietary and owned by Dynalist Inc., the company behind the product. The source code is not publicly available for inspection, modification, or redistribution under any open source license.

This surprises some users because Obsidian feels like an open ecosystem. It's built on web technologies (it runs on Electron), has a thriving plugin community, and gives users full ownership of their data in plain Markdown files. But feeling open and being open source are two different things.

What Obsidian's License Actually Says

Obsidian uses a proprietary license with a tiered model:

• Free for personal use — individuals can use it at no cost
• Paid license required for commercial use — businesses and organizations need to purchase a license
• Catalyst license — an optional supporter tier that gives early access to insider builds

The free personal tier is generous, which is part of why many people assume it must be open source. But "free to use" and "open source" are fundamentally different concepts. Open source refers specifically to whether the source code is publicly available and whether users have the right to view, modify, and distribute it — not to whether the software costs money.

The Plugin System: Open Source Adjacent, Not Open Source Core

Here's where things get genuinely interesting. While Obsidian's core is closed, its plugin and theme ecosystem is largely open source by community convention. Most community plugins are hosted on GitHub under open licenses, and Obsidian's plugin API is publicly documented.

This creates an unusual split:

So while you can't inspect how Obsidian itself renders your notes or manages its sync infrastructure, the plugins extending its functionality are often fully transparent and community-auditable.

Why This Matters Depending on How You Use It 🔍

Whether Obsidian's proprietary status is a dealbreaker depends heavily on your use case and priorities.

For privacy-conscious personal users, the key consideration is usually data, not code. Obsidian stores your notes locally by default in plain .md files, which means no vendor lock-in on the file format itself. Even if the app disappears, your data remains readable by any text editor or Markdown-compatible tool.

For security researchers or enterprise teams, a closed core means you cannot audit the code for vulnerabilities or compliance with internal policies. Some organizations require open source software specifically so their security teams can review it — Obsidian doesn't meet that bar.

For developers who want to extend the tool, the open plugin API provides significant flexibility without needing core access. Many power users build sophisticated workflows entirely through community plugins without ever needing to touch the underlying application code.

For users comparing Obsidian to alternatives, it's worth knowing that some competitors are fully open source. Logseq, for example, has an open source codebase. Joplin is another fully open source note-taking option. These tools appeal to users for whom code transparency is a hard requirement.

Local-First vs. Open Source: Two Different Things ⚙️

Obsidian is often described as local-first software, meaning your data lives on your device rather than in the cloud by default. This is a meaningful privacy feature — but it's not the same as being open source.

Local-first means:

• Your files don't live on Obsidian's servers unless you opt into Obsidian Sync (a paid feature)
• You can access, move, back up, and migrate your notes without the company's involvement
• You're not dependent on an internet connection or the company staying in business to read your own notes

Open source means something different:

• The underlying code is publicly available
• Independent parties can inspect it, fork it, or contribute to it
• Licensing permits redistribution and modification under defined terms

Obsidian gives you the first set of benefits but not the second. That combination — local data ownership with a closed core — sits in a distinct category that doesn't map neatly onto either a traditional SaaS product or a fully open source tool.

The Variables That Shape Your Evaluation

Whether Obsidian's licensing model works for your situation comes down to factors that are genuinely specific to you:

• Your technical requirements — Do you need to audit source code for compliance or security reasons?
• Your organizational policies — Some workplaces restrict software to approved open source or enterprise tools only
• Your data portability needs — Markdown files are highly portable; Obsidian Sync data adds a cloud dependency if you use it
• Your tolerance for vendor dependency — A proprietary core means you're relying on Dynalist Inc. to maintain the product
• Your use of the plugin ecosystem — If you depend heavily on community plugins, those are generally auditable even if the core isn't

The combination of these factors means two people asking the same question — is Obsidian open source? — may land in completely different places once they apply the answer to their own situation.