Online UML Diagram Tool

CNET Editors' Rating:

Design better software with better tools

Start Free

Create UML Diagrams

SmartDraw helps you plan software projects with the help of UML diagrams. Start with the exact UML template you need. SmartDraw has templates for class diagrams, use case diagrams, sequence diagrams, state diagrams, activity diagrams, and more. Add boxes and components with a few clicks, add your information, and our UML diagram software does the rest, aligning everything and applying professional design themes for great results every time.

Top reasons SmartDraw is perfect tool for UML diagrams:

Automated Diagrams from Data
SmartDraw's Class Extension lets you build a UML class diagram automatically using your source code on GitHub or a local repository. No drawing required. Learn more about SmartDraw class diagram maker.
Intelligent Formatting
Add or remove a shape, and our UML diagram software realigns and arranges all the elements so that everything looks great.
Works on Any Device
Use SmartDraw on your computer, browser or mobile device—Windows^®, Mac^®, Android^®, iOS^®, or any other platform with an internet connection. Whether you're in the office or on the go, you'll enjoy the full set of features, symbols, and high-quality output you get only with SmartDraw.
Quick-Start UML Templates
Dozens of professionally-designed UML diagram examples make you instantly productive. Simply choose the template that is most similar to your project, and customize it to suit your needs.
Free Support
Have a question? Call or email us. SmartDraw experts are standing by ready to help, for free!

SmartDraw even lets you create a class diagram from your source code automatically.

All you need to do is point it at your repository or load your source code and choose which files you want to include in your diagram. Click "Build Diagram" and you're done. It's that easy.

No need to build diagrams by hand when SmartDraw does it for you. Learn more about generating class diagrams automatically.

Effortless Collaboration

You and your team can work on the same UML diagram by sharing it on your included online account or by using your favorite file sharing apps like Dropbox^®, Google Drive^®, Box^® or OneDrive^®. You can also share files with non SmartDraw users by simply emailing them a link.

Smart Integration

You can simply share your UML diagram in a variety of common graphics formats such as a PDF or PNG.

You can also export your UML diagram to any Office^® or G Suite^® application in just a few easy clicks.

SmartDraw also has apps to integrate with Atlassian's Confluence, Jira, and Trello. You can easily make a class diagram and share it in your Confluence documentation or attach a use case diagram to a Jira issue.

SmartDraw integrates with the tools you use

UML Diagram Templates Included

The biggest advantage to using SmartDraw are the templates and examples included. If you are just starting out, you may also find our examples helpful before building your first UML diagram.

Activity Diagram - Order Processing

Class Diagram - Web Transactions

Try SmartDraw Free

Discover why SmartDraw is the perfect UML diagram tool.

Start Now