Gliffy

Commercial

Create and share a class diagram, sequence diagram, or any UML diagram with free UML diagram software.

Drawing a professional-looking UML diagram (Unified Modeling Language Diagram) is simple with this free UML diagram tool. Just drag and drop from a library of shapes to show any of the nine UML diagrams needed to model a system. Since no single diagram can model a system completely, the free UML diagram editor makes it easy to add more diagrams as you need them.

Create, Share and Collaborate with Free UML Diagram Software:
Use case diagram
Class diagram
Object diagram
State diagram
Activity diagram
Sequence diagram
Collaboration diagram
Component diagram
Deployment diagram
See UML diagram examples

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