ExcalidrawTurn rough ideas into diagrams, wireframes and sketches.
Free editor. No account or drawing quota.
Design & creative
PlantUML
Free optionOpen sourceLocal
Turn text definitions into UML, sequence, timing and activity diagrams.
What you can use it for
Turn text definitions into UML, sequence, timing and activity diagrams.
- Store editable diagram source with your project files.
- Generate technical diagrams locally without a document subscription.
Workflow coverage and comparison notes
Create and update individual technical flowcharts, UML and sequence diagrams. Does not replace hosted team canvases, all business diagram templates or proprietary file interchange.
Before you switch
Technical installation and diagram syntax required; some diagram types need Graphviz. Use a local installation for confidential diagrams, since public rendering sends the source to a server. No shared whiteboard, drag-and-drop designer or full editable Visio import compatibility.
Alternatives to these paid apps
Each comparison covers the workflow described above, rather than every paid feature.
More for the same workflow
See alternatives →Excalidraw
tldrawSketch ideas, brainstorm and draw diagrams on a shared browser whiteboard.
tldraw.com is a free collaborative whiteboard (site title: 'free and instant collaborative whiteboarding').
Draw flowcharts, system diagrams and process maps in your browser.
'Free forever, no sign-up required' (site); Apache-2.0; desktop app too.