How to Open & Read .mm Files Online (Free, No Download)
Someone sent you a .mm file and your computer has no idea what to do with it. Before you go hunting for a decade-old desktop installer, here's the short version: you can open, read, and even edit .mm files online, in your browser, for free.
What is a .mm file?
A .mm file is a mind map. It's the native format of FreeMind, the classic open-source mind mapping app, and it's also read and written by Freeplane, its popular successor. Despite the intimidating extension, a .mm file is just plain-text XML — a tree of <node> elements describing your central idea, its branches, notes, icons, and links.
That's good news: because it's an open text format, any modern tool can read it. You don't need the exact program that created it.
The fastest way: open it in your browser
CloudMindMaps reads the FreeMind .mm format natively. There's nothing to install and no account required just to view a file.
- Go to cloudmindmaps.app.
- Drag your
.mmfile straight onto the page — or click Open file and pick it. - The map renders instantly, fully laid out and interactive. Zoom, pan, fold branches, and read notes.
Because it runs locally in your browser, the file never has to leave your machine to be viewed. Reading a map is completely private.
Have a .mm file open right now?
Drop it into CloudMindMaps and read it in seconds — free, no sign-up to view.
Open a .mm file →Reading vs. editing
Plenty of "viewers" only show you a static picture. CloudMindMaps is a full editor, so once your file is open you can actually do something with it:
- Restructure it — drag nodes, add children, fold and unfold branches.
- Search inside it — jump to any node by typing part of its text.
- Follow links and notes —
.mmnodes often carry hyperlinks and long-form notes; both come through. - Export it back — save as
.mmagain to stay compatible with FreeMind and Freeplane, or export an image or outline to share.
Keep it in the cloud (optional)
If you sign in with Google, you can save the map to your account and get a shareable link. That turns a lonely file on your hard drive into something you can send to a colleague, embed in a doc, or pick up later on another device. We wrote more about that in FreeMind in the Cloud.
Frequently asked questions
Can I open a .mm file on my phone?
Yes — CloudMindMaps runs in mobile browsers, so you can open and read a .mm attachment on iOS or Android without any app.
Is a .mm file the same as a Mermaid or Markdown map?
No. .mm here refers to the FreeMind/Freeplane XML format, not Mermaid diagrams or Markdown. If your file starts with <map version=...> when you open it in a text editor, it's a FreeMind map.
Will my formatting survive?
Node hierarchy, notes, links, and most styling come through cleanly. If a rare node looks off, the underlying XML is still intact and re-exportable.