Free Class Diagram Generator Online

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Free Class Diagram Generator Online

Design object-oriented structures with classes, interfaces, inheritance, and associations.

What is a Class Diagram?

A class diagram is a UML diagram that shows the structure of a system by depicting classes, their attributes, methods, and the relationships between them. It's a fundamental tool for object-oriented design, helping developers plan code architecture before implementation.

Common Use Cases

  • Software design - Plan class hierarchies and relationships
  • Database modeling - Map entities to object models
  • API design - Define data transfer objects and services
  • Documentation - Communicate system architecture to teams
  • Code generation - Use diagrams as blueprints for implementation

Syntax Quick Reference

ElementSyntaxDescription
Classclass Name { }Define a class
Attribute+String nameClass property (+ public, - private)
Method+method()Class function
Inheritance<|--Extends relationship
Composition*--Contains relationship
Association-->Uses relationship

Export Options

PNG Export

High-resolution images for documents and presentations.

SVG Export

Scalable vectors for web and further editing.

PDF Export

Print-ready format for professional documentation.

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