The note board
Start here. Sticky notes with no structure at all: write fast, move them around, join the ones that belong together. What you joined arrives on the map already shaped.
/ A little thought. A world of possibility. /
Free online
mind mapping.
Aster is a free mind map maker for brainstorming ideas, planning projects and organising study notes. Connect your thoughts in the browser, collect the loose ends, and save the whole thing as a file you own. No account or installation needed.
Start mapping
Nothing to install. Bookmark your mind map workspace.
No accountNo subscriptionNo AI insideSave to your device
/ Three surfaces, one file /
Brainstorm, map
and plan.
Raw thoughts do not arrive in order. Start where there are no rules, and turn it into structure once you can see it.
The map
Where it becomes a shape. Branches lay themselves out as you type. Fold the detail away, focus one branch, connect ideas across the tree.
The plan
Where it becomes work. Mark a node a question, a decision or something to do. Every parent counts what is done beneath it, and the plan reads it back as a list.
/ Bring your own AI /
Mind mapping with
your own AI assistant.
Most tools pick a model for you and hide it behind a button. That throws away everything you have already built up in your own assistant: the project you have been discussing for weeks, the documents you uploaded, the instructions you set.
Aster writes the prompt and reads the reply back. Your assistant, your model, your account, your context. Aster does not send your map to an AI service automatically. You choose what to copy and share, with no API key required by Aster.
Only share what you are comfortable sending to your chosen provider. Its terms apply.
- Pick a branch and a task.
Expand it, ask what is missing, challenge it, find the themes, improve the wording, or turn it into actions. Aster copies a prompt carrying the branch, its path and the map title.
- Take it to your assistant.
Paste it wherever you already work. Copy the reply.
- Review before anything changes.
Paste the reply back and Aster shows you every proposed change, one line each, before a single word touches your map. Undo is always there.
/ Where your thinking lives /
Save your mind maps
as your own files.
Save it where you keep everything else. Open it again months later. No account to make, nothing syncing quietly to a server you do not own.
- One file holds the map, its notes, the board and the marks.
- An optional browser recovery copy can help restore unsaved work. Save a map file to keep a reliable copy.
- Export a Markdown outline when the thinking has to become writing.
/ From a thought to a map /
How to make a mind map online.
Start with one question, topic or goal. Build out the details as your thinking develops.
Choose your central idea
Open the free mind map workspace and edit the central idea. Try a topic you are studying, a project you are planning, or a problem you want to untangle.
Add branches and connections
Add a child for each main theme, then add supporting ideas beneath it. Attach notes and links, rearrange branches, and connect related ideas across the map. Use the note board for thoughts you want to organise later.
Save your map and keep going
Choose Save map to write a file to your device. Use Open to return to it later, or export a Markdown outline when you want to turn the map into writing.
For an essay, branch into your argument, evidence and questions. For a project, map goals, tasks and dependencies. For revision, connect concepts and add notes in your own words.
/ Before you start /
Questions about Aster.
Is Aster free, and do I need an account?
Aster is a free personal project. You can create and edit mind maps without signing up or paying a subscription. Start a mind map directly in your browser.
How do I save and reopen a mind map?
Choose Save map to save a JSON map file on your device. It includes your branches, notes, connections, note board and marks. Choose Open and select that file to continue. Markdown export gives you an outline for writing, rather than a full copy of every map feature.
Where is my map stored?
Aster does not automatically upload or sync your maps to a cloud account. You choose where to save the map file. An optional recovery copy of unsaved work is stored in this browser; turn off “Recovery copy on this device” in the menu to remove it. Recovery depends on browser storage and map size, so save your work to a file regularly. See the privacy information in German for hosting and other data processing.
Can I use Aster offline?
Once the workspace is loaded, you can keep working on your map without an internet connection. Opening or reloading Aster offline is not guaranteed. Save your map before closing the tab.
Does Aster use AI automatically?
No. Aster helps you copy a prompt from a selected branch to an assistant you choose. You paste the reply back and review the proposed changes before applying them. The prompt can include your map title and branch content, so check it before sharing. See how the AI workflow works.
Can I share a map or work on it with someone else?
You can send a saved map file to someone else, and they can open their own copy in Aster. Aster does not provide real-time collaborative editing or automatic synchronisation between copies.
/ A note from the maker /
Why I made this.
Stefan MokrosCreator of Aster
I wanted somewhere to untangle a problem that did not ask me to sign up, did not decide which model I should use, and did not keep my thinking on someone else's server.
So Aster stays small. It helps you get a thought out of your head and into a shape you can work with, and then it gets out of the way. This is a free personal project, and seeing how other people use it is the best way to make it better.
Tell me what you are thinking ↗What's the thought on your mind?
Start mapping