Choosing a free UML tool


I have decided to write this article for college undergraduate, small sized company that would like to have free UML modeling tool that is required for software design. I believe that comparison is not enough as it is but you need always to specify the context you are doing the comparison for, and usually comparison factors have different weights to each one.


Low budget company or student who would like to have tool for drawing UML diagrams to the latest specs as much as possible, also being able generate documentation for the tool viewable by other colleges or having a viewer for its diagrams. Code generation will be very good option, but mainly sharing the design as images to be able to communicate it to others is the most important.

Modelio Papyrus Astah
Supported UML version Yes, 2.4.1 Yes, 2.5 2.1 to 2.5 based on user request.
Use-case diagram Yes Yes Yes
Class diagram Yes Yes Yes
Object diagram Yes Yes, as variation of class diagram, refer to this forum thread. Yes
Sequence diagram Yes Yes Yes
Collaboration / Communication diagram Yes Yes Yes
State diagram Yes Yes Yes
Package diagram Yes, through class diagram. Yes Yes
Component diagram Yes, through class diagram. Yes Yes
Activity diagram Yes Yes Yes
Export diagram to image Yes Yes Yes
Publish to Web (Export to HTML) Yes, free edition Web Model Publisher. Not by itself, need either modeling gendoc or BIRT, based on this thread. Quite complex. Yes, professional version
Publish to rtf or doc Yes, professional edition, Document Publisher, but expensive 400 Euro. Not by itself, need either modeling gendoc or BIRT, based on this thread. Quite complex. Yes, professional version
Based on Standard IDE Eclipse RCP framework Eclipse No, seems Java based product only.
UML to code generation (Languages) Yes (Java) Yes (Java, C/C++, ADA) Yes (Java, C++, C#), but professional version only.
Reverse Engineer code to UML Yes (Java) Yes (Java) Yes (Java), but professional version only
Model checking (Pre-defined/Customizable) -- TODO -- -- TODO -- -- TODO --
Model checking (While saving/On Demand) -- TODO -- -- TODO -- -- TODO --
XMI version (Import & Export) Yes, OMG UML 2.1.1 -> 2.4.1 (From Preferences -> XMI) Yes, 2.1 Yes, but for professional version only
Started since 2009 2008 1999 as JUDE, and renamed to Astah 2009
Release activity Major release every 1.5 or 2 years
Bug fix release: around 4 per year.
1 Major release is planned across 1 year, minor releases are quite few. No major release since 2009, but most of minor releases has new features, and around 2 - 5 minor releases per year.
Latest release & date v3.1.2 (2014-05-20) v1.0.0 (2014-06-25) v2.8 (2014-02-13)
Has Enterprise version for future upgrade. Yes No Yes
Forum activity Between low and average Above average Between low and average
Extendable and marketplace Yes Extendable but not marketplace. Yes
Integration with Atlassian Confluence No No Yes, for server edition free, not available for cloud
Windows installer Yes Yes, eclipse based just as update Yes
Mac OS installer Yes, instruction here. Yes, eclipse based just as update No
Linux installer Yes Yes, eclipse based just as update No
iPad version No No Yes, iOS 8
Download link here, around 200 MB here, around 330 MB for Eclipse Modeling Tools, then papyrus 94 MB. here, around 60 MB
Youtube channel ModelioCommunity Papyrus Eclipse ChangeVision Astah
General comment
  • Tool is quite good.
  • Its help is great and search on Internet gets quick answer.
  • Community had a lot of answers to my questions.
  • Require some learning curve for adding and hiding elements.
  • Documentation is not complete.
  • Tutorial is outdated since 2010.
  • Although download components separately, it took more than 3 hours installing eclipse and Papyrus, even was not responding several minutes.
  • It is quite comprehensive & having lots of features.
  • Very hard from usability perspective.
  • Require longest time learning curve.
  • Much smaller than other releases.
  • Lightweight tool.
  • Not good interface.
  • Simple in creating attributes, operations.


I have decided to use Modelio for the moment and will keep posting feedback to the page.For anyone viewing this blogpost, take the above table as a base and add whatever factors you would like to have in the tool, and complete the comparison and decide for yourself, I believe the above list contains the best free UML tools as by the time of writing this blogpost.

I'm open for discussion and feedback.

Discarded Products

Product name
Reason for disqualification
Visual Paradigm - community edition Community is full featured but limited to one diagram per diagram type.
Argo UML Not maintained since 2011.
BOUML It became licensed software.
TopCoder UML tool Last activity in May 2013, after stopping around 3 years.
Gaphor Only UML 2.0 support.
Dia It seems not maintained anymore.
NClass Not maintained since 2010 although its GUI is very good.
yEd Supports only class diagram& object diagram.
Umbrello Only UML 2.0 support.
Poseidon for UML community Only UML 2.0 support.
Star UML 2 Old version has lot of adaptation, but new version which seem complete re-write is still under development. It seems might be very good choice in near future

Comparison References


  1. Thanks for this. I have not used any of the above tools. In additoin you might consider ParadigmPlus and Enterprise Architect, both which have free community editions for students, I believe.

    Another feature of interest is model checking capabiliies; are there rules which may be customized? Are the diagrams checked in real-time, or does the user need to produce a reoprt?

    1. Hi,

      Modelio has checking capabilities than can be customized. More info about the ckecking tool (audit tool): http://forge.modelio.org/projects/modelio3-usermanual-english-310/wiki/Modeler-_modeler_handy_tools_model_audit. More information about how to configure it (http://forge.modelio.org/projects/modelio3-usermanual-english-310/wiki/Modeler-_modeler_managing_projects_configuring_project_audit). The audit is processed in real-time when you modify the model from the uml browser or from the diagram view.

      For the other tools, I can't say if they have the same functionalities.


    2. I will make another post for commercial product, both products mentioned are not free and their free verison is limited as per the post, the student version is also low priced not free, and My intention was not student more than low budget small computer startups.



      I think the features you have added are quite good to be added and checked across tools, In Shaa Allah, I will do soon.

  2. Thank you very much for your article, it's really interesting.
    Manuel Mata