Notion alternatives: compare AFFiNE, Docmost and SiYuan

Start with the workflow you need to move. A team wiki, a visual planning space, and a personal knowledge base need different things from a Notion alternative. Use the comparison below to shortlist AFFiNE, Docmost, or SiYuan, then test a small export before moving your workspace.

Evidence scope: this is a documentation-based comparison, not a hands-on migration benchmark. The original feature table is a September 2, 2026 snapshot. The September 8 revision adds a migration acceptance kit and rechecks the linked Docmost import guide and AFFiNE project overview. No candidate has been run through the full acceptance kit for this article.

Which candidate should you investigate first?

• Team documentation: investigate Docmost if moving a page-based workspace is the priority. Its import guide documents a Notion ZIP import path. That makes it a useful pilot candidate; it does not establish that your databases or permissions will survive.
• Documents and visual planning: investigate AFFiNE if the workflow combines writing with a canvas. Its project overview describes documents and whiteboards together. Include canvas content in your exit test.
• Personal knowledge work: the original SiYuan assessment below focuses on a personal workspace. Verify its current collaboration and access model against your team requirements before extending that fit to shared work.

Download the workspace migration acceptance kit (ZIP): an editable CSV worksheet and a step-by-step pilot plan. All result cells start as “not tested.” This is not a Notion export file.

What "alternative" actually has to match

An alternative does not have to match Notion's feature page. It has to match your workflows: the meeting notes, the wiki, the database your team actually opens every day. Before you compare candidates, it is worth knowing exactly how portable your current content is, from Notion's own documentation.

Workspace export covers HTML, Markdown, and CSV for databases, plus your uploaded files. That is the good news. The fine print matters more. Notion states plainly that you can't instantly recreate your workspace by reuploading exported content. Download links expire after 7 days, and exports can take up to 30 hours to process. On Enterprise plans, workspace or teamspace owners can disable member exporting entirely. And workspace PDF export is being removed, with rollout through 31 August 2026.

None of this is a complaint. It is documented behavior, and it sets the bar: any candidate you evaluate should export your data in a form you can re-import elsewhere, on your schedule.

The original product observations below were checked on September 2, 2026; they are not a claim about the latest release or edition today.

A checklist that works for any candidate

Run these five checks before you fall in love with a demo. They apply to any self-hosted tool, the three below included.

1. License. Read the LICENSE file, not the badge. Monorepos sometimes split licenses by directory, and "core" licenses can hide enterprise-gated features.
2. Deployment model. Find the official install path. Docker Compose, Kubernetes, single binary. Note every dependency it drags in: databases, caches, proxies.
3. Data export. What formats come out, and can a restore get your content back? A backup that only restores one component is not a full exit.
4. Project activity. Check the releases page and issue tracker. Look at dates, not stars. Recent, steady releases beat a big number that stopped moving.
5. Maintenance burden. Who upgrades it, backs it up, and watches it at 2 a.m.? If the answer is "nobody yet", that is your answer.

Documentation comparison: September 2, 2026 snapshot

I applied the checklist to three candidates on September 2, 2026. Sources: the AFFiNE repository and self-host docs, the Docmost repository and installation docs, and the SiYuan repository with its releases.

Notion stays as the context row in your head: whatever you pick, the migration path out of it is the export behavior described above.

Why the usual suspects are missing

You will notice some famous names absent. That is the checklist working, not an oversight.

AppFlowy-Cloud was archived on 1 September 2026. The README calls it legacy and unmaintained, and says production self-hosting is a closed-source commercial fork with a free tier of one user seat. Outline's LICENSE is Business Source License 1.1, which states in its own text that it is not an Open Source license (its change date to Apache-2.0 is 2030-09-01). Wiki.js 3.0.0-beta.537 is explicitly marked not for production use; v2.5.314 is the production latest.

Run a small migration acceptance test

Use a disposable workspace containing no sensitive material. Record the candidate version and edition; repeat the same checks for every candidate. Decide which checks are mandatory before testing.

1. Prepare a representative sample. Include a parent page, two child pages, internal links, an image, an attachment, and a small database using the views and relations you actually need. Record the original counts and permissions.
2. Export and import. Use the products’ supported flows. A successful import message is only the beginning: open the imported pages and inspect their content.
3. Check the workflow. Follow internal links, open attachments, search for a known phrase, and repeat a normal database task. Record missing features and repair time.
4. Check access with separate users. Confirm that a viewer cannot edit and an uninvited user cannot open private material. Do not assume source permissions migrated.
5. Test the exit and recovery. Export again and inspect the files independently. Separately, restore a backup into a fresh instance and confirm that text, attachments, and required settings return.

Mark each worksheet row pass, fail, or not tested. If a mandatory workflow fails, keep that candidate out of a full migration until the gap is resolved. An untested requirement stays an open question.

Our recommendation: pilot the candidate whose documented workflow fits your main use case, and let the mandatory checks decide whether to continue. A feature checklist cannot establish migration fidelity or operating cost.

For the earlier adoption decision, use the repository evaluation guide. More comparisons and practical guides live at Open Source.

Caveats

• Feature tables rot fast. The checked-at date of September 2, 2026 bounds every claim here, including versions and star counts. Re-verify before you rely on any of them.
• License nuance: Docmost and SiYuan are AGPL-3.0, which carries network-copyleft implications a company should run past counsel. This is not legal advice. AFFiNE CE is described as MIT, but the backend carries a separate license.
• No candidate here is "the winner". Fit depends on your constraints: team size, compliance, who is on call.

Disclosures

• First-party interest: ranex.dev is my site, and this series covers the open-source ecosystem I work in.
• AI assistance was used in the research and drafting of this post.
• The September 8, 2026 revision was AI-assisted. Human review of this revision has not been recorded. The migration worksheet is an unexecuted test plan, not a report of a completed migration.

FAQ

Is AFFiNE really MIT licensed?

Mostly, for the Community Edition. AFFiNE CE is described as MIT and free for self-hosting, but the repository LICENSE is split: packages/backend and packages/common/native carry a separate license, and the EE server code requires a valid Enterprise Edition subscription for production use. Read the LICENSE files yourself before committing.

Which candidate is closest to Notion?

None is a full replacement. Docmost is the most team-oriented of the three, but its Bases feature (Table and Kanban) is Enterprise-only as of v0.95.0. AFFiNE's official backup procedure is a Postgres pg_dump plus blobs rather than a document export. SiYuan describes itself as a privacy-first personal knowledge system, and its official Docker hosting cannot export PDF, HTML, or Word.

What about AppFlowy?

The AppFlowy-Cloud repository was archived on 1 September 2026. Its README calls it legacy and unmaintained, and says production self-hosting is now a closed-source commercial fork with a free tier of one user seat. That is why it is not in the table.

Will my Notion content migrate cleanly?

Partly. Non-database pages export as Markdown and full-page databases as CSV, with callouts becoming HTML. But you cannot export all database views at once, Form views cannot be exported, and Notion states you cannot instantly recreate a workspace by re-uploading exported content. Databases, views, and permissions will not round-trip.