Open Source Mind Mapping Software
A mind map is thinking made visible, but the map you draw in an afternoon is worthless if you can't get the structure back out as an outline, a list, or a file another tool understands. The open source apps here treat the map as structured data rather than a drawing, exporting to plain outlines, OPML, or images, so the connections you spotted survive outside the canvas that captured them.
AFFiNE
Local-first open-source workspace that merges docs, whiteboards, tables, and AI as a Notion and Miro alternative
Trilium Notes
Hierarchical note-taking app for large personal knowledge bases, with local use and self-hosted sync
SimpleMindMap
Web mind map library and software with self-hosting, local file support, and many import-export formats
DesktopNaotu
Offline desktop mind map tool based on Baidu Mind Mapping, with cross-platform support for Windows, Linux, and macOS
Freeplane
Open source mind mapping software for organizing ideas, notes, and project work
Heimer
Cross-platform mind map and diagram app with auto layout, XML save files, and export to PNG or SVG
WiseMapping
Free open-source mind mapping tool for creating and collaborating on visual maps online
Mindolph
Open source personal knowledge management software with AI support for mind maps, markdown, PlantUML, and text
VYM
Mind mapping software for visualizing ideas, tasks, and complex contexts