What Duck.ai is
AlternativeTo files Duck.ai under AI Chatbot, Large Language Model (LLM). It is recorded as Freemium, Proprietary, from United States. It ships on Mac, Windows, Online, Android, iPhone, Android Tablet, iPad. The topics its entry raises are privacy, chat and large language models.
That is our reading of the record. For AlternativeTo's own wording, see its page for Duck.ai — the facts above were read on 2026-08-16.
| Price | Freemium |
|---|---|
| Licence | Proprietary |
| Category | AI Chatbot, Large Language Model (LLM) |
| Origin | United States |
| Platforms | Mac, Windows, Online, Android, iPhone, Android Tablet, iPad |
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 | Duck.ai |
|---|---|---|
| Price | $1/month, one plan, 7-day trial without a card | Freemium |
| Licence | Proprietary | Proprietary |
| Platforms | macOS, Windows, iOS, Android | Mac, Windows, Online, Android, iPhone, Android Tablet, iPad |
| Category | Note-taking — AI chat into Markdown | AI Chatbot, Large Language Model (LLM) |
| Where notes live | Standard .md files in a folder you choose | AlternativeTo does not say |
| AI model | Seven providers, always on your own API key | Its description mentions AI |
| Origin | Poland, EU | United States |
Where they differ
- Duck.ai is a place to have the conversation. SumizAI is not a chatbot — the conversation is the input, not the product. What comes out of it is a
.mdfile with a title, a place inbase.mdand a duplicate check against the notes already in the vault. If you only want to talk to a model, you do not need SumizAI. - Duck.ai is freemium: there is a free tier and a paid one, and the line between them is the thing to read before committing. SumizAI has one plan at a dollar a month, so there is no feature held back for a higher tier — and an unpaid account still opens and exports every vault it already has.
- AlternativeTo's description of Duck.ai does not mention Markdown, so check what format your notes end up in before you fill it up. SumizAI writes standard
.mdfiles to a folder you picked, and an unpaid account can still export all of them.
Which one to pick
Reasons to pick Duck.ai
- you need it to run in a browser
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 Duck.ai: AlternativeTo, read 2026-08-16. SumizAI is not affiliated with Duck.ai, and the name is used only to identify the product being compared.
Taken from the AlternativeTo lists: ChatGPT.