What Zen Notes is
AlternativeTo lists Zen Notes without a category. It is recorded as Free, Open Source — MIT. It ships on Mac, Windows, Linux. The topics its entry raises are Markdown and collaboration.
That is our reading of the record. For AlternativeTo's own wording, see its page for Zen Notes — the facts above were read on 2026-08-16.
| Price | Free |
|---|---|
| Licence | Open Source — MIT |
| Category | AlternativeTo does not say |
| Origin | AlternativeTo does not say |
| Platforms | Mac, Windows, Linux |
What SumizAI is
A note-taking application built around a conversation with an AI model. You ask a question, the answer streams back, and the answers worth keeping become Markdown notes — filed into a vault that is a folder on your own disk.
A vault is a directory holding base.md, a generated table of contents up to six levels deep, and a notes/ folder with one .md file per note. Before a note is written it is checked against the ones already there, so the fourth note about the same idea gets merged instead of added. Links between notes are ordinary Markdown links to files that exist.
The model is never ours: you bring your own API key to one of seven providers — Anthropic, OpenAI, Gemini, Groq, OpenRouter, a local Ollama or your own server — and pay that provider directly. A question sends the table of contents plus at most five relevant notes within a 24,000-character budget, and the app shows you which five it used.
Side by side
| Side by side | SumizAI | Zen Notes |
|---|---|---|
| Price | $1/month, one plan, 7-day trial without a card | Free |
| Licence | Proprietary | Open Source — MIT |
| Platforms | macOS, Windows, iOS, Android | Mac, Windows, Linux |
| Category | Note-taking — AI chat into Markdown | AlternativeTo does not say |
| Where notes live | Standard .md files in a folder you choose | Its description mentions Markdown |
| AI model | Seven providers, always on your own API key | Its description does not mention AI |
| Origin | Poland, EU | AlternativeTo does not say |
Where they differ
- AlternativeTo's description of Zen Notes does not mention an AI model. That is the whole starting point in SumizAI: you have a conversation with a model on your own API key, and the answers worth keeping become notes without you filing them.
- Zen Notes is open source (MIT), and SumizAI is not. If reading the source is what decides it for you, that is a real argument for Zen Notes. The guarantee SumizAI offers instead is structural rather than legal: the notes are Markdown files in a folder you chose, so they open in any editor whether or not the application is running.
- Both keep Markdown, which makes moving between them mostly a matter of copying files. In SumizAI a vault is a directory holding
base.md— a generated table of contents — and anotes/folder with one.mdfile per note. - Zen Notes is described as something more than one person uses at once. SumizAI is not: there are no shared vaults, no comments, no permissions and no sync between devices. If the work is a team's, that is a reason to pick Zen Notes over SumizAI.
- AlternativeTo lists no mobile version of Zen Notes. SumizAI runs on macOS, Windows, iOS and Android.
Which one to pick
Reasons to pick Zen Notes
- the source is open and you want to read it
- it costs nothing
- more than one person works in the same notes
Reasons to pick SumizAI
- the notes you want already exist inside conversations with an AI model
- you want the filing — title, chapter, duplicate check — to happen without you
- you want the result as plain
.mdfiles in a folder you picked - you would rather pay your AI provider directly than have a note app resell the model
Facts about Zen Notes: AlternativeTo, read 2026-08-16. SumizAI is not affiliated with Zen Notes, and the name is used only to identify the product being compared.
Taken from the AlternativeTo lists: Obsidian.