Introduction
draw.io is a free, open-source diagramming application that runs entirely in the browser. It supports flowcharts, network diagrams, UML, ER diagrams, and more with no account required and no data leaving your machine.
What draw.io Does
- Creates professional diagrams with a drag-and-drop visual editor
- Supports dozens of diagram types including flowcharts, UML, ER, network, and org charts
- Stores files locally, on Google Drive, OneDrive, Dropbox, or GitHub
- Exports to PNG, SVG, PDF, VSDX, and XML formats
- Integrates with Confluence, Jira, Notion, and VS Code
Architecture Overview
draw.io is a client-side JavaScript application. The editor runs entirely in the browser using mxGraph as the rendering engine. The Docker image bundles a Tomcat server that serves the static frontend. No server-side processing of diagram data occurs, making it privacy-friendly by design.
Self-Hosting & Configuration
- Deploy via Docker:
docker run -d -p 8080:8080 jgraph/drawio - Configure with environment variables for CSP headers and export settings
- Set DRAWIO_SELF_CONTAINED=true to disable external resource loading
- Use DRAWIO_SERVER_URL for custom domain configuration
- Supports HTTPS via reverse proxy with Nginx or Traefik
Key Features
- Fully offline capable with no data sent to external servers
- Over 100 built-in shape libraries covering AWS, Azure, GCP, Cisco, and UML
- Desktop versions available for Windows, macOS, and Linux via Electron
- Plugins for VS Code, Confluence, Jira, and Google Workspace
- Import and export Visio (.vsdx) files directly
Comparison with Similar Tools
- Excalidraw — Hand-drawn style whiteboarding; draw.io offers more formal diagram types and shape libraries
- Lucidchart — Commercial SaaS with collaboration; draw.io is free and fully self-hostable
- Mermaid — Text-based diagram generation; draw.io provides a visual WYSIWYG editor
- yEd — Desktop-only diagramming tool; draw.io runs in any browser with cloud storage options
- PlantUML — Code-to-diagram for UML; draw.io covers broader diagram types with a visual interface
FAQ
Q: Is draw.io truly free? A: Yes. The core application is free and open source under the Apache 2.0 license with no usage limits or premium tiers.
Q: Can I use draw.io without an internet connection? A: Yes. The desktop app works fully offline, and the self-hosted Docker version requires no external connectivity.
Q: Does draw.io store my data on its servers? A: No. Diagrams are processed entirely in the browser. Storage is handled by your chosen backend such as local disk, Google Drive, or GitHub.
Q: How do I migrate from Visio? A: draw.io can import .vsdx files directly. Open the file via the import menu and the diagram will be converted automatically.