head to head · open source
SiYuan vs Outline
SiYuan has 47,039 GitHub stars, 3,095 forks, 18 open issues and last shipped yesterday. Outline has 41,145 stars, 3,650 forks, 78 open issues and last shipped yesterday. SiYuan leads on adoption by 14% (47,039 vs 41,145 stars). SiYuan is written in TypeScript under AGPL-3.0; Outline is written in TypeScript under a custom or non-standard licence. SiYuan has attracted 7% as many forks as stars, Outline 9%. SiYuan was the more recently maintained of the two, and both are self-hostable with no licence fee.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| SiYuan | Outline | |
|---|---|---|
| GitHub stars | ★ 47K | ★ 41K |
| License | AGPL-3.0 | Custom / other |
| Written in | TypeScript | TypeScript |
| Last push | 2026-11-02 | 2026-11-02 |
| Forks | ⑂ 3.1K | ⑂ 3.6K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick SiYuan if
- You weight community size — 47K stars and counting
- You want the AGPL-3.0 license terms
- Your stack matches TypeScript
- You value the larger contributor base for long-term maintenance
pick Outline if
- You want the Outline feature set and don't need the biggest community
- You prefer the Custom / other license terms
- Your stack matches TypeScript
- You evaluated both and Outline fits your workflow better
About SiYuan
From thought to insight, with agents English 中文 日本語 Türkçe Table of Contents 💡 Introduction 🔮 Features 🏗️ Architecture and Ecosystem 🗺️ Roadmap 🚀 Download Setup App Market Installation Package Package Manager Docker Hosting Unraid Hosting TrueNAS Hosting Test Channels ⌨️ Command line Interface 🏘️ Community 🛠️ Development Guide ❓ FAQ How does SiYuan store data? Does it support data synchronization through a third party sync disk? Is SiYuan open source? How to upgrade to a new version? What if some blocks (such as paragraph blocks in list items) cannot find the block icon? What should I do if the data repo…
read the full SiYuan overview →
About Outline
A fast, collaborative, knowledge base for your team built using React and Node.js. Try out Outline using our hosted version at www.getoutline.com . This is the source code that runs Outline and all the associated services. If you want to use Outline then you don't need to run this code, A hosted version of the app is offered at getoutline.com. You can also find documentation on using Outline in our guide. If you'd like to run your own copy of Outline or contribute to development then this is the place for you. Installation Please see the documentation for running your own copy of Outline in a production…
read the full Outline overview →
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Frequently asked questions
Is SiYuan or Outline more popular?
SiYuan has 47,039 GitHub stars and Outline has 41,145. SiYuan has the larger community by that measure.
Are SiYuan and Outline free?
Both are open source. SiYuan is licensed under AGPL-3.0, and Outline has no licence declared in this registry. Both are free to self-host.
What is the difference between SiYuan and Outline?
SiYuan is written in TypeScript and Outline in TypeScript. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, SiYuan or Outline?
Choose SiYuan if you want the larger community (47,039 stars) or its AGPL-3.0 licence terms. Choose Outline if its feature set, stack or Custom / other licence fits better. Both are self-hostable.