PlantUML is an open-source tool that allows users to create diagrams from plain text using a simple and intuitive syntax. It supports a wide range of diagram types, including:
Supported UML Diagrams
With PlantUML, you can create well-structured UML diagrams, including but not limited to:
- Sequence diagram
- Usecase diagram
- Class diagram
- Object diagram
- Activity diagram
- Component diagram
- Deployment diagram
- State diagram
- Timing diagram
Key Features
- Simple syntax: PlantUML uses a plain text syntax that is easy to read and write.
- Support for multiple diagram types: PlantUML supports a wide range of diagram types, making it a versatile tool for various use cases.
- Integration with popular tools: PlantUML can be integrated with popular tools like Eclipse, Visual Studio, IntelliJ, and more.
- Online editor: PlantUML provides an online editor that allows users to create and share diagrams without installing any software.
- Open-source: PlantUML is open-source, which means it is free to use, modify, and distribute.
A sample UML Sequence Diagram as Code
@startuml
' Define the actors and systems
actor User as "User"
participant "Web Browser" as Browser
participant "Web Application" as App
participant "Database" as DB
' Define the login sequence
Browser->>App: Request login page
App->>Browser: Return login page
User->>Browser: Enter credentials
Browser->>App: Submit credentials
App->>DB: Verify credentials
DB->>App: Return verification result
App->>Browser: Return login result
' Define the database-driven operations sequence
Browser->>App: Request data
App->>DB: Retrieve data
DB->>App: Return data
App->>Browser: Return data
@enduml
URL for Online PlantUML Editor: https://www.plantuml.com/plantuml/uml/SyfFKj2rKt3CoKnELR1Io4ZDoSa70000
Rendered Diagram as output of the code

Tip: You can even prompt popular GenAI models to generate the PlantUML code for you based on your requirement!