Diagrams.net — Mind Mapping & Diagramming Tool

Diagrams.net remains one of the best free diagramming tools available, especially when privacy, local storage control, and open-source access matter.

Diagrams.net, also widely known as draw.io, is a free open-source diagramming application. Its official positioning emphasizes security-first diagramming, user-controlled storage, no required sign-up, and support for many technical and business diagram types.

You can use diagrams.net for flowcharts, UML, ER diagrams, network diagrams, process maps, org charts, database schemas, and architecture visuals.

• Broad diagram support across technical and business formats
• Free, open-source, and no-signup browser use
• Privacy-first storage model with local or chosen cloud storage
• Strong import/export support for common diagram workflows

• Outstanding free value
• Excellent for technical diagramming
• Storage and privacy model are better than many cloud-first tools

• Interface can feel utilitarian rather than elegant
• Collaboration flow is less polished than some team-first platforms
• Not as beginner-friendly as simpler visual tools

Diagrams.net is best for developers, IT teams, analysts, teachers, and anyone who needs serious diagramming without vendor lock-in or subscription pressure.

For related diagramming workflows, compare diagrams.net with Lucidchart, Whimsical, and Miro.

Is diagrams.net really free? Yes. Free and open-source access are core to the project.

Why do technical teams like it? Because it is capable, privacy-conscious, and not artificially restricted.

June 27, 2026.