Free Open Source UML Tools

"UML is not dessert topping and floor wax." - Grady Booch on the versatility of UML.

UML as you know, includes a set of graphic notation techniques that helps you specify, visualize, and document models of software systems, including their structure and design, in a way that meets all of these requirements. There are many popular professional diagramming tools like Visio available in the market. Depending on your need, sometimes you don’t really need commercial tools to generate UML diagrams. This article contains some Good Open Source UML tools that might do the job for you for free.

StarUML - StarUML is an open source project to develop fast, flexible, extensible, featureful, and freely-available UML/MDA platform running on Win32 platform. The goal of the StarUML project is to build a software modeling tool and also platform that is a compelling replacement of commercial UML tools

Check it’s features here

ArgoUML - ArgoUML is the leading open source UML modeling tool and includes support for all standard UML 1.4 diagrams. It runs on any Java platform and is available in ten languages.

Check its features here.

Violet UML Editor - Draws nice-looking diagrams. Completely free. Cross-platform.Violet is intended for developers, students, teachers, and authors who need to produce simple UML diagrams quickly.

Check its features here.

Astah Community 6.1 (Previously JUDE)- Based on the concept of "Usable from the moment of installation", the modeling features of astah community have been designed to be simple and user friendly.

Check its features here


BOUML - BOUML is a free UML 2 tool box allowing you to specify and generate code in C++, Java, Idl,Php and Python. BOUML runs under Unix/Linux/Solaris, MacOS X(Power PC and Intel) and Windows.

Check its features here.

UMLet 10.4 - UMLet is an open-source UML tool with a simple user interface: draw UML diagrams fast, export diagrams to eps, pdf, jpg, svg, and clipboard, share diagrams using Eclipse, and create new, custom UML elements. UMLet runs stand-alone or as Eclipse plug-in on Windows, OS X and Linux.

Check its features here

UMLGraph - UMLGraph allows the declarative specification and drawing of UML class and sequence diagrams. The current features are part of an ongoing effort aiming to provide support for all types UML diagrams.

Check its features here


Dia - Dia is a GTK+ based diagram creation program for GNU/Linux, Unix and Windows released under the GPL license. Dia is roughly inspired by the commercial Windows program 'Visio', though more geared towards informal diagrams for casual use. It can be used to draw many different kinds of diagrams.

Check its features here.


MetaUML - MetaUML is a GNU GPL MetaPost library for typesetting UML diagrams, using a human-friendly textual notation.

UML Modeling Tools for IDE’s

Here are some community edition modeling tools available for popular IDE’s.

Visual Paradigm SDE for Visual Studio - Smart Development Environment Community Edition for Visual Studio (SDE-VS CE) fully supports the latest version of UML. Open source projects' developers can use SDE-VS CE to design system with UML. SDE-VS CE is free non-commercial use only. SDE-VS is embedded in Visual Studio

Check its features here.


T4 Editor plus UML modeling Tools for Visual Studio (2008/2010) - Quickly write your own Code Generator via T4 Text-Templates (.tt-Files) with Intelli-Sense & Syntax-Highlighting. tangible T4 Editor also comes with UML-Style modelingtools and can generate from diagrams, database schemas, xml, word, excel sources, or any other data source. Microsoft T4 looks and smells like ASP.NET - it is simple!

Check its features here


NetBeans IDE UML - The UML plugin for the NetBeans IDE is available for version 6.7 and earlier releases.

Check its features here


Eclipse UML2 Tools - UML2 Tools is a set of GMF-based editors for viewing and editing UML models; it is focused on (eventual) automatic generation of editors for all UML diagram types

Check its features here

Some Online UML Diagram Generators

Here are some free web based diagram generators

WebSequenceDiagram - Just enter the description here, and click "draw"

yUML - Create and share simple UML diagrams in your blogs, wikis, forums, bug-trackers and emails

zOOml - is the Web 2.0 site for rapid object-oriented modeling. It's easy to create a model's Modeler web application, a drawing tool for illustrating classes, associations and other concepts in OMG's UML modeling language.

About The Author

Suprotim Agarwal
Suprotim Agarwal, Developer Technologies MVP (Microsoft Most Valuable Professional) is the founder and contributor for DevCurry, DotNetCurry and SQLServerCurry. He is the Chief Editor of a Developer Magazine called DNC Magazine. He has also authored two Books - 51 Recipes using jQuery with ASP.NET Controls. and The Absolutely Awesome jQuery CookBook.

Follow him on twitter @suprotimagarwal.


z said...

nice list but you forgot

Aleksey Tsalolikhin said...

What a useful article! Thank you so much! Aleksey

John said...

You left out cacoo

Platform independent, don't need to install it on your computer.. completely portable

ah, the cloud.

Unknown said...

Quick Sequence Diagram Editor -

Written in Java. "Quick Sequence Diagram Editor is a tool for creating UML sequence diagrams from textual descriptions of objects and messages that follow a very easy syntax."

I use it all the time.

Anonymous said...

declarative sequende diagram editing

Anonymous said...

You forgot UMBRELLO:

Beben Koben said...

hmmm...for what is it???
hihihihi :D
btw its sure a usefully, thanks :)

Peter Mularien said...

Thanks for the great list. There were a few here that I had never heard of / tried before.

Anonymous said...

PlantUML is another text based UML tool

Meta Coral said...

You forgot Gliffy. Comes in very handy when you don't have the luxury of having a tool installed on your machine.

Suprotim Agarwal said...

Thank you all for letting users know about these additional UML tools. Keep the comments coming :)

Unknown said...

Hello, Would you please to make some references to the original sources for this articles.

And I want to share with you another this site: <a href="> CASE Tools </a> is a site devoted to CASE Tools, I think it could be useful to find another tools which aren't on this articles.

kind regards.

Unknown said...

See EasyUML Editor

EasyUML Editor is a Web based Editor which generates UML Diagram from easy to use textual notation.

Marc said...

Veeeery uselful, couldn't find a list like this one ANYWHERE on the net!
good thing you've got the visualizations for each, helps a lot.

pan said...

Modelio is now open source! Check it at Modelio open source website

Anonymous said...

BOUML is no longer free. Went to their website and found you must purchase it.

nhp91 said...

Thank you !

Evan said...

Good list. I would like to add Creately to your collection. Its not a open source software but a free to try UML diagramming software

Selrahc's Gold said...

A couple more for your list from Eclipse: Papyrus and Papyrus for Real time.

Esportista urbano said...

As someone commented, I recommend PlantUML for developing applications that need to generate UML diagrams, it has its own language and covers a lot of diagrams.