The Best UML Diagramming Tool Available

When UML modeling drives your development process, you need a tool that is specifically designed for UML and will give you all the features you need – without being too complicated. That’s Astah UML. A simple to learn, simple to use tool, Astah UML will allow you to create the UML diagrams you need.
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Modern UML Diagramming

Designed with UML 2.x in Mind.

Astah is even faster than Excel or non-UML specific drawing tools. And our software will allow you to create a set of UML 2.x diagrams for your project, including:

Class diagrams

UseCase diagrams

Statemachine diagrams

Activity diagrams

Sequence diagrams

Timing diagrams

Communication diagrams

Component diagrams

Deployment diagrams

Composite Structure diagrams


Powerfully Easy

Work quickly and efficiently with assist functions.

We’ve been incorporating user feedback for more than 10 years. The result is a powerful software program that is incredibly easy to use and learn. Astah UML offers a variety of “assist” functions to make your work faster, including:

Auto-create class diagrams
Alignment guides
Copy to MS Office documents
Customize shortcut keys
Gap expander/remover
Map view
Merge project files
Search and replace
Show related classes/models
State transition path & table

Make it Your Own

Big library of plug-ins & integrations.

Need a feature that’s not included out of the box? No problem! Thanks to the Friends of Astah and our own extensive library of plug-ins and integrations, Astah UML can be customized to do what you need. Plug-ins are available for code generation, reverse engineering code, exporting, usability, and more. In addition, Astah UML integrates with miro, plantUML, yUML and Freemind and more!

Expand the power with our API.

The Astah API enables you to obtain Astah model information, create and modify diagrams and models, and use them in application software. With our API guide, you can also create your own plug-in and submit it to our library!

Go Above & Beyond

Reverse engineer or generate code

Bring your model to life by generating code directly from your diagram with our code generation tools. Or work backwards and reverse engineer your project to create a model. Astah UML supports reverse engineering of Java, C#, and C++.

Import and export

Modeling is an amazing means of communicating your ideas, but you may need to get that information out of Astah UML and into the hands of your colleagues. With Astah UML, you can export diagrams to a variety of formats, including image files (jpg, png, emf, and svg), RTF documents, and HTML. You can also copy and paste into Microsoft Office documents and print with customized settings.

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Diagramming tool for individuals & teams of all sizes

Astah’s tools allow you to create a wide variety of diagrams and offer flexible pricing based on your needs. Whether you’re a student just starting out, part of an enterprise-wide development team, or an academic faculty member, we have a package that is right for you!

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Trusted & Used Worldwide

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Want More? Go Pro!

Astah UML is a powerful tool in its own right, especially when you’re a student, working independently, or just getting started with modeling. However, if you want more functions, consider upgrading to Astah Pro. It offers all the features of Astah UML plus more!

Wide Variety

More Types of Diagrams

In addition to the UML 2.x diargams, create ER diagrams, flowcharts, and requirement diagrams in Astah Pro.
UML Diagrams

Collaboration for Bigger Teams

Pro offers collaborative modeling features that are effective when working with large-scale or remote teams.
Team Collaboration

Multi Language Support

Let each model have dual names – English & Portuguese, German, etc. Particularly helpful for offshore development.
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Additional Licensing Options

More licensing options are available with Astah Pro, including perpetual licensing and academic discounted licensing.