Short answer
The best open source note taking apps in 2026 are Joplin for one person on every device, Logseq for linked daily notes, Trilium for a large personal knowledge base, Standard Notes or Notesnook for encryption, Memos for a quick log, AppFlowy for a Notion-style workspace, and Baalda for a team editing markdown on its own server.
For one person, Joplin is the best open source note taking app in 2026, with Logseq, Trilium, Standard Notes, Notesnook, Memos and AppFlowy each winning a narrower job. For a team, the answer depends on a layer most lists never open: the server the notes sync through, and whether its licence lets a business run it. Baalda is the pick when a team wants markdown files and a server of its own with no seat cap.
Most lists stop at the licence badge on the app. That badge is accurate and it is not the whole answer, because the moment notes leave one laptop they go through a sync server, and on several of these projects the server sits under different terms from the app. For one person that rarely matters. For a company of five it decides whether "open source" means you can run the thing for your team at all. Baalda, the app this site is for, is on the list for that second reader, and every licence below was checked against the project's own LICENSE or README file on 24 October 2026.
Which open source note taking apps are worth using?
| App | App licence | The server you sync through | Best for |
|---|---|---|---|
| Joplin | AGPL-3.0-or-later | Joplin Server: personal, non-commercial licence. Or any cloud folder | One person, every platform |
| Logseq | AGPL-3.0 | Your own file sync for file graphs. RTC for DB graphs is in alpha | Outlining and daily notes |
| Trilium | AGPL-3.0 | Self-hosted sync server, same licence | A deep personal knowledge base |
| Standard Notes | AGPL-3.0 | Self-hostable, GPL-3.0. Premium features need a subscription | Encrypted notes |
| Notesnook | GPL-3.0 | Sync server AGPL-3.0, self-hosting "without support" | Encrypted notes, newer stack |
| Memos | MIT | Memos is the server | A quick personal or shared log |
| AppFlowy | AGPL-3.0 | Commercial self-host server, free tier of one seat | A Notion-style workspace |
| Baalda | Apache-2.0 | Apache-2.0, no vault or member limits when self-hosted | A team editing markdown together |
Obsidian is not on the list because it is not open source. Its notes are plain markdown, which is why it shows up in these round-ups anyway, and Is Obsidian open source? covers exactly which parts are closed.
Why check the server licence and not just the app?
Because the app licence covers the program on your laptop, and a team lives on the server. Three of the apps above show the gap clearly.
Joplin. The repository's LICENSE says all code is AGPL-3.0-or-later "unless a directory contains a LICENSE or LICENSE.md file". packages/server contains one: the Joplin Server Personal Use License, dated 21 December 2021. It allows use "for personal non-commercial purposes only", and its list of things a licensee may not do includes granting access "for a fee or free of charge if the Licensee is a legal or natural person engaged in commercial activities". A company running Joplin Server for its staff needs written permission from Joplin first. The app itself is still a fine open source pick, and it syncs to Nextcloud, Dropbox, OneDrive and others with end-to-end encryption, so a solo user never has to touch the server.
AppFlowy. The client is AGPL-3.0. The open source server, AppFlowy-Cloud, is now archived on GitHub, and its README says it "is no longer used to build or distribute the latest AppFlowy self-hosted server". Self-hosting moved to AppFlowy-SelfHost-Commercial, distributed under the AppFlowy Self-Hosted Commercial License and built from what the README calls the "commercial AppFlowy Cloud codebase". Its free tier is "One User Seat (per instance)" plus up to 3 guest editors. More people means a paid self-hosted plan.
Standard Notes. The server is open and self-hostable with Docker. Standard Notes' own help page says that to reach server-side premium features "you'll need to create a subscription for your account", that a subscription created that way unlocks "server side premium features, but not client-side premium features", and that the full set needs an offline plan.
None of this is a trick. These are small companies paying for development, and the terms are published. The point is that "open source note taking app" and "open source notes my team can run on its own server at no cost" are different searches, and most round-ups answer the first while the reader meant the second.
What does each one do best?
Joplin
The safe default for one person. Markdown notes in notebooks, apps on desktop and mobile, end-to-end encrypted sync to storage you already pay for, and a long track record. Real-time co-editing is not what it is for.
Logseq
An outliner built around daily journals and links between blocks. File graphs are markdown files on your disk, so any sync tool works. The newer DB version stores graphs in a database, and Logseq's README says "the DB version is in beta status while the new mobile app and RTC is in alpha", with the warning that "data loss is possible". Pick the file version if you want stability today.
Trilium
The most capable personal knowledge base here: deep note trees, scripting, note types, and sync to a server you host yourself under the same AGPL licence. Its documentation says your data "is stored in a SQLite database" called document.db, with Markdown as an import and export format, so the notes are not a folder of files you can open in another editor.
Standard Notes and Notesnook
The two to pick if encryption is the requirement. Both encrypt notes end to end, which also means the server cannot read or index them for you. Notesnook's sync server is AGPL-3.0, and its README says self-hosting "is now possible, but without support" while documentation is still to come.
Memos
Less a notebook than a timeline of short notes, written in markdown, and a self-hosted server from the first minute. MIT licensed, one Docker command to start, and the lightest thing on this list to run for a small group.
AppFlowy
Projects, wikis and docs in one workspace, which its own repository describes as "the leading open source Notion alternative". Good for one person or for evaluation on the free self-host tier. A team of more than one seat should read the self-hosted pricing before committing.
Baalda
A team second brain. Notes are plain .md files in a folder on each person's disk, several people edit the same note at once over a CRDT, folders and files carry their own Viewer and Editor permissions, and an AI assistant reads and writes the same files over MCP. Everything in the repository outside the ee/ directory is Apache-2.0, including the sync server, and contributions come in under the same licence with no CLA. As of 24 October 2026 ee/ holds only its README and LICENSE: no feature code sits behind the commercial licence yet.
Can a team run Baalda's server itself?
Yes, and that is the reason it is on this list. Baalda's deployment guide says a self-hosted server runs with billing switched off, "so there are no vault or member limits". The managed service has a Free plan for 2 people and 1 synced vault and a Team plan at $10 per seat per month; your own server has neither cap.
The easiest route is the baalda-server template on Railway, which the deploy guide walks through:
- Click Deploy on Railway. It creates two services, Postgres and the Baalda server, and generates the secrets.
- Copy the server's web address, which looks like
https://something.up.railway.app. - Open the Baalda desktop app. Before the first sign-in it asks where your notes live. Choose your own server and paste the address.
- Send your team
https://<your-address>/open/connect. One click connects their app.
Railway bills you for what the server uses. Developers can run the same server from Docker or the Compose bundle in deploy/compose; it is one Node service plus Postgres. Each person still keeps the vault as markdown files on their own disk, so the server holds the shared copy and the permissions, not the only copy. For what changes once a self-hosted server has more than one user in it, see Owning the server is the easy half of self-hosted shared notes.
Which one should you pick?
- Just you, every device: Joplin.
- Just you, thinking in outlines and daily notes: Logseq, the file version.
- Just you, a large structured knowledge base: Trilium.
- Encryption first: Standard Notes or Notesnook.
- A quick shared log on a box you already run: Memos.
- A Notion replacement for one person: AppFlowy.
- A team that wants to edit the same markdown notes live, on a server it controls, with an AI that can read them: Baalda.
If your shortlist also includes closed apps, the Obsidian alternatives round-up sorts them by what you keep when you leave.
Where is Baalda the wrong choice?
For a lot of people, honestly. It is desktop only, on macOS, Windows and Linux, with no phone app, so anyone who writes most of their notes on a phone should look at Joplin or Notesnook. It is not end-to-end encrypted: the server indexes note text so search and the MCP tools work, which is the opposite trade from Standard Notes. It is young, at version 0.1.87 on 22 October 2026, against projects with many years of releases behind them. And a single person with no plans to share a vault gains little from a sync server at all; any of the solo picks above will serve them well.
Where it does fit is the gap the server licences leave: a team that wants plain files, live co-editing and its own server, under a licence that lets a business run it for everyone without asking.