Excalidraw has a distinct look: lines and shapes appear as if drawn by hand, which lowers the pressure to make diagrams perfect and encourages quick sketching. It runs in the browser without an account. You draw boxes, arrows, and text, drop in shapes from libraries, and share a link so others can edit with you in real time. It’s popular with developers for architecture sketches and with teachers and designers for brainstorming.
The tool is intentionally simple. It supports export to PNG, SVG, and its own file format, end-to-end encrypted collaboration, and embedding in documentation and tools such as Obsidian, Notion, and VS Code. A paid version, Excalidraw Plus, adds persistent workspaces, more storage, and team features. AI features can generate diagrams from a text description, which you can then edit by hand.
Excalidraw is free and open source under the MIT license, so teams can self-host it. It isn’t designed for polished, formal diagrams or large documents, and features like advanced layout are minimal. Alternatives include draw.io for formal diagrams, Miro and FigJam for team whiteboards, tldraw, which is another open-source canvas, and Lucidchart. Excalidraw suits quick, collaborative sketching.