Discover the Best 36 Open-Source Apps for UML Design
UML, or Unified Modeling Language, is a standard language used in software engineering to create visual models of software systems. It provides a set of graphical notations to represent different aspects of a software system, such as its structure, behavior, and interactions.
One of the most common uses of UML is to create use-case diagrams. A use-case diagram is a type of UML diagram that represents the interactions between a system and its users. It shows the different actions that users can perform with the system and the different responses that the system provides. Use-case diagrams are useful for identifying the requirements of a system and for communicating those requirements to developers and stakeholders.
In summary, UML is a powerful tool for software engineers that allows them to create visual models of software systems. Use-case diagrams are one of the most common types of UML diagrams and are used to represent the interactions between a system and its users.
Some real-world examples of applications of UML are:
- Air Traffic Control Systems: UML is used to model and describe the interactions between different components of an air traffic control system.
- Banking and Financial Systems: UML is used to model and design banking and financial systems, including online banking systems, credit card processing systems, and stock trading systems.
- Healthcare Systems: UML is used to model and design healthcare systems, such as electronic medical record systems and hospital management systems.
- E-commerce Systems: UML is used to model and design e-commerce systems, including online stores, shopping carts, and payment processing systems.
- Automotive Systems: UML is used to model and design automotive systems, including engine control systems, navigation systems, and safety systems.
UML provides a powerful set of tools for modeling and designing complex software systems in a variety of industries.
In this post, we offer you a list of he best open-source and free UML design tools that you can download and use totally for free.
1- UMLet
UMLet is a great choice for those who need a free and user-friendly UML tool. With its simple and intuitive interface, you can quickly create UML diagrams without the need for extensive training or experience with other software. UMLet offers a wide range of export formats, including EPS, PDF, JPG, SVG, and clipboard, making it easy to share your diagrams with others in a variety of ways.
In addition, UMLet integrates with Eclipse, a popular development environment, allowing you to seamlessly incorporate your diagrams into your existing projects. And if you need to create custom UML elements, UMLet has you covered with its easy-to-use element creation tool. Overall, UMLet is an excellent choice for anyone looking for a powerful, yet easy-to-use UML tool that won't break the bank.
2- Gaphor
Gapher is a reliable, user-friendly, and completely free program that allows users to create UML and SysML diagrams with ease. The software is compatible with all major operating systems, including Windows, Linux, and macOS, ensuring that everyone can benefit from its powerful features. With Gapher, users can create clear and concise diagrams that accurately represent their systems and processes, making it an essential tool for software engineers, architects, and developers alike.
Whether you are working on a small project or a large-scale application, Gapher can help you visualize your ideas and bring your vision to life. With its intuitive interface and a wide range of features, Gapher is the perfect choice for anyone looking to create high-quality UML and SysML diagrams without spending a dime.
3- E.R.A simple UML
This is a simple UML design software that can work with minimal hardware requirements, and it supports exporting your diagram to PDF.
4- Violet
Violet is an intuitive and user-friendly UML editor that has a lot of benefits. It is specifically designed to cater to the needs of developers, students, teachers, and authors who require a tool to create simple UML diagrams in a quick and efficient manner.
One of the most significant advantages of Violet is that it is incredibly easy to learn and use, even for beginners who have no prior experience in using such software. The interface is user-friendly and intuitive, providing a seamless experience from start to finish.
5- Dia
Dia is a fantastic open-source tool that empowers you to design and build intricate technical diagrams with ease. From flowcharts to network diagrams, Dia has got you covered. The best part? It is completely free! Whether you are a student, a professional, or just someone who loves to tinker with diagrams, Dia is the perfect tool for you.
It is highly versatile and can be installed on all major operating systems including macOS, Windows, and Linux. Once you start using Dia, you will never go back to any other diagramming tool!
6- ArgoUML
ArgoUML is an open-source UML modeling tool that supports the latest standards of UML. It is written in Java and is available for Windows, Linux, and macOS. With ArgoUML, you can design and create complex UML diagrams with ease. The software is user-friendly and intuitive, making it easy for beginners to get started. ArgoUML also offers a wide range of features, including class diagrams, use case diagrams, sequence diagrams, and more.
It is a great choice for software developers, architects, and engineers who need a reliable and powerful UML modeling tool without breaking the bank.
7- Umletino
UMLetino is a reliable and user-friendly online UML tool that is accessible through your web browser, eliminating the need for any time-consuming and complicated installations. It is based on UMLet, a powerful diagramming tool that is available both as a stand-alone program and as an Eclipse plugin, and shares its speedy, text-based way of creating UML sketches.
With UMLetino, users can enjoy a variety of amazing features, including the ability to create various types of UML diagrams with ease. Additionally, it offers simple, markup-based UML element modifications, which can be done in a straightforward and hassle-free way. Users can also take advantage of the tool's PNG export option, which makes sharing and incorporating the diagrams into presentations and reports a breeze.
8- JetUML
JetUML is a software application that provides users with the ability to create and manipulate UML diagrams. The tool is designed to be lightweight and easy to use, making it a popular choice among developers and other professionals who require a reliable UML editor.
One of the key features of JetUML is that it is completely free, which makes it an ideal choice for those who are working within a tight budget. Additionally, the app is built using Java technology, which means that it can be run on a wide range of platforms without requiring any additional software.
9- StarUML
StarUML is a powerful and versatile software engineering tool that has been designed to provide system modeling capabilities using the Unified Modeling Language (UML), as well as the Systems Modeling Language (SysML), and classical modeling notations. Developed and published by MKLabs, the software is available on multiple operating systems, including Windows, Linux, and MacOS, and is widely used by software developers and engineers around the world.
In addition to its comprehensive modeling capabilities, StarUML also offers a wide range of powerful features and tools that make it an essential tool for any software development project. These include support for code generation, reverse engineering, and round-trip engineering, as well as support for a wide range of programming languages, including Java, C++, and Python.
10- Umple
Umple is a modeling tool that is open-source and designed for software developers and students. It allows for the creation of UML quickly within the classroom, and is available both as an online eclipse plugin and as a standalone command-line Jar.
Umple is a model-oriented programming technology that adds UML associations and state machines to Java and PHP. It enables the creation of UML diagrams, models that are embedded in code, and the generation of a complete system.
It is licensed under the MIT license.
11- System Designer
System Designer is a versatile open source application that makes designing complex systems and system components easy. It features a user-friendly interface and uses the Unified Modeling Language (UML), an industry-standard modeling language widely used in software development.
Additionally, System Designer employs MSON, a JSON-based format, to store and organize your system designs. With MSON, you can easily define types, classes, relationships, and even multi-inheritance between classes, making it easy to bring your ideas to life.
12- Modelio
Modelio is a robust modeling solution that provides a plethora of functionalities. With its focus on enterprise architecture, software development, and systems engineering, Modelio adheres to the latest industry standards. It boasts a user-friendly interface and is highly customizable, allowing users to tailor the software to their specific needs. Additionally, Modelio offers a diverse range of features such as diagram creation, code generation, and model validation, making it an all-encompassing modeling tool.
Modelio features highlight
- UML Modeler : Modelio is a first and foremost a modeling environment, supporting a wide range of models and diagrams, and providing model assistance and consistency-checking features.
- BPMN support integrated with UML : Modelio combines BPMN support and UML support in one tool, with dedicated diagrams to support business process modeling.
- Java code generator : The Java Designer module uses an RCP/Eclipse-style project file structure, and supports Java code generation and reverse, Javadoc generation and Java automation.
- XMI import/export : Modelio provides an XMI import/export feature that enables you to exchange UML2 models between different tools.
- HTML model publishing : With the HTML Publisher module, publish your models in HTML format.
- Extension system : Modelio can be extended for any language, methodology or modeling technique just by adding modules to your configuration. You can either use existing modules or else develop your own.
- Scripting language support (Jython) : Modelio provides integrated support of the Jython scripting language, for online requests, small scripts and macro definition.
Supported Standards
- UML2 : UML2 is a general-purpose modeling language from the OMG, used in the field of object-oriented software engineering.
- BPMN2 : BPMN is a standard for business process modeling, providing a graphical notation for the specification of business processes.
- Archimate : Archimate is an open and independent enterprise architecture modeling language to support the description, analysis and visualization of architecture within and across business domains.
- XMI :XMI is an OMG standard used in the exchange of metadata information via the XML language.
- MDA : MDA is an OMG standard, which implements and uses model extensions in the development of software systems.
- TOGAF :TOGAF is an enterprise architecture framework, providing a complete approach to enterprise information architecture design, planning, implementation and governance.
13- Diagramo
Diagramo - pure HTML5 JavaScript diagram / flowchart editor
14- PlantUML
PlantUML is an open-source tool used for creating UML diagrams from plain text descriptions. It supports a wide range of diagram types, including class diagrams, use case diagrams, sequence diagrams, and more. With PlantUML, you can create diagrams quickly and easily using a simple text-based syntax. In addition, PlantUML offers a range of export options, including PNG, SVG, and PDF, making it easy to share your diagrams with others.
Some of its features include:
- Support for a wide range of diagram types
- Simple, text-based syntax for creating diagrams
- Multiple export options, including PNG, SVG, and PDF
- Integration with various programming languages and tools
- Cross-platform compatibility
Overall, PlantUML is a powerful and versatile tool that can help you create high-quality UML diagrams quickly and easily.
PlantUML is a component that allows to quickly write:
- Sequence diagram,
- Use case diagram,
- Class diagram,
- Object diagram,
- Activity diagram (here is the legacy syntax),
- Component diagram,
- Deployment diagram,
- State diagram,
- Timing diagram.
15- Open ModelSphere
OpenModelSphere is the ultimate open-source modeling tool that empowers users to effortlessly create and design UML diagrams with confidence. Its exceptional versatility allows for endless applications, from software development to business modeling and systems engineering.
With its intuitive user interface, OpenModelSphere is a breeze to use, even for beginners. Not to mention its vast array of features, including diagram creation, code generation, and model validation, making it the all-encompassing modeling tool of choice.
16- Archi - ArchiMate Modelling Editor
Archi® is a free, open source, cross-platform tool and editor to create ArchiMate models.
The Archi® modelling tool is targeted toward all levels of Enterprise Architects and Modellers. It provides a low cost to entry solution to users who may be making their first steps in the ArchiMate modelling language, or who are looking for a free, cross-platform ArchiMate modelling tool for their company or institution and wish to engage with the language within a TOGAF® or other Enterprise Architecture framework.
ArchiMate® is an open and independent Enterprise Architecture modelling language that supports the description, analysis and visualization of architecture within and across business domains. ArchiMate is one of the open standards hosted by The Open Group and is fully aligned with TOGAF®.
17- NClass
NClass is a free tool to easily create UML class diagrams with C# and Java language support. The user interface is designed to be simple and user-friendly for easy and fast development. Initially the project was developed by the great Balasz Tihanyi on sourceforge, but the project has gone inactive due the lack of time.
Still, NClass is a great tool, although it is missing some important features. The goal of this project is to restart the development of NClass, adding the missing features.
Features highlight:
- C# and Java support with many language specific elements
- Simple and easy to use user interface
- Inline class editors with syntactic parsers for easy and fast editing
- Source code generation
- Reverse engineering from .NET assemblies (thanks to Malte Ried)
- Configurable diagram styles
- Printing / saving to image
- Multilingual user interface
- Mono support for non-Windows users
18- go-diagram
A UML diagram editor for Golang projects.
19- UMLreader
This project is a simple means to read a UMLetino diagram file by parsing and retrieving the various sections
The project is designed to be run either by Main.py or by withClasses.py. You should provide the name of the .uxf file you wish to parse as the first CLA.
20- SketchUML
SketchUML is a pen-based interaction UML (Unified Modeling Language) diagram editor, which converts the shapes user drawn into software UML objects.
To use SketchUML, the user first imagine the shape of a figure and draw it on the software. The software then recognizes the stroke and provides a list of objects the user likely means. The user selects the object he/she truly means from the list. SketchUML convert the stroke into software object according to the selection, and the user could edit on the properties of the object.
SketchUML is written entirely in Java and it can be installed on Windows, Linux, and macOS.
21- UML-editor
The idea is to implement visual diagram editor that allows to create UML class diagrams and generate source code out of them.
22- mar.ink
This project offers a Mermaid diagram viewer and editor.
23- TinyUML
TinyUML is a free and user-friendly software tool that enables the creation of UML 2 diagrams in a matter of seconds. It provides an intuitive interface that makes it easy to use even for those who are not familiar with UML.
This software is exclusively implemented for the Java platform, which guarantees high performance and reliability. To ensure that the program runs smoothly, it is recommended to have at least Java SE 6 installed on your computer.
Platforms: Windows, Linux, and macOS.
24- TextChart
TextChart is an open-source project that uses diagrams as code conspt. It is a simple mobile first editor for UML diagrams built using AWS Lambda, Google Cloud Kubernetes, DynamoDB etc.
25- JDL-Studio
JDL-Studio is an open-source self-hosted online tool for drawing UML diagrams for JHipster based on the JDL syntax. It tries to keep its syntax visually as close as possible to the generated UML diagram without resorting to ASCII drawings.
You can download and install it using Docker and run it as a web app, on your local machine or a remote server.
26- CollabUML
CollabUML is a PlantUML self-hosted based app for online collaborative design on UML
27- nomnoml
This is nomnoml, a tool for drawing UML diagrams based on a simple syntax. It tries to keep its syntax visually as close as possible to the generated UML diagram without resorting to ASCII drawings. The nomnoml javascript library can render diagrams on your web page. The only dependency is graphite. Install nomnoml using either npm or good old script inclusion. In the SVG output the node name is attached to SVG shapes and g containers with data-name attribute. You can use this to implement interactive diagrams.
Features highlight
- HTML Canvas rendering target
- SVG output in NodeJS
- Command Line Interface
- Web application
- Custom classifier styles
- The nomnoml javascript library can render diagrams on your web page
28- Apricot DB
"Apricot DB" is a database tool for design and analysis of the relational database structure. It represents the DB- structure in the form of editable Entity/Relationship Diagrams (ERD). "Apricot DB" allows to perform reverse engineering on the existing database, as well as to create a new database structure from scratch. Allows to generate the essential DDL- scripts for CREATE/DROP/DELETE- operations based on the current ERD.
Features
The lightweight and easy-to-use Entity/Relationship Diagram (ERD) design tool
- The Reverse Engineering of all major databases
- Export of the Diagrams into PNG, PDF of MS Excel format
- Stores the multiple versions of the same database structure
- Find and analyze the differences between versions/environments of the database
- The automatic generation of all major DDL scripts from ERD
- The team work: sharing Apricot Projects via Git repository. Import/Export of the Projects
- Support of the "Crow's Foot" and IDEF1x ERD notations
- The automatic optimization of the allocation of objects on the diagram
29- WhiteStarUML
WhiteStarUML is a fork of StarUML 5.0 providing a number of bug fixes and improving compatibility with modern operating systems.
Features
- Refreshed user interface
- Fully functional handling of UNICODE strings
- Diagrams may be enhanced with antialiased drawing and images
- Java reverse engineering updated to version 1.5 (thanks to Frank Hernandez)
- ERD Profile is directly integrated and extended to generate and parse SQL tables
- Improved support for large projects - units may be loaded and unloaded on demand
- 64-bit build is available (some plugins were not ported)
- Developed and tested on Windows 7, 8 and 10
30- Firefly UML
Firefly UML is a 100% pure Java application designed to create and edit UML conform diagrams. With class diagrams, sequence and instance diagrams, Firefly UML provides a solid selection from the vast range of existing UML diagram types.
Firefly UML is really easy to learn as it provides you multiple ways of access to the same function - be it mouse action, hotkey, context menu or toolbar icon. And the best thing is: once you have learned how to handle one type of diagram, you also have learned how to deal with the other diagram types, because they all follow the exactly same user interaction patterns.
Features highlight
- Easy to learn and use
- Runs on Windows, Linux, and macOS
- Tailor-made for Java developers who want quick diagrams for their code
- Import existing Java projects and let Firefly do the work for you
- Create and modify class models from scratch directly within Firefly
- Export your models into skeleton Java code
- Supports Class diagrams, Sequence diagrams and instance diagrams
- Firefly enables you to share the same classes in multiple diagrams in your project - change one, and the others will update automatically
- Project support enables you to keep your files together and quickly load previous projects
- Fast and powerful custom rendering engine based on SWING
31- epp uml
Epp (Emines++) UML is a UML tool aimed at providing a fast way of creating UML diagrams, it is a free, open-source UML tool with a simple user interface: draw UML diagrams fast, export diagrams to jpg, png, and clipboard.....
32- SINVAS UML
SINVAS is a software engineering platform tool to support Full Life Cycle of software development, and is composed of five products.
SINVAS acquires Traceability, recyclability and visibility of software development.
It will help greatly to the improvement of productivity and product quality.
33- CodeDesigner
CodeDesigner is free and open-source RAD tool suitable for easy creation of various diagrams describing applications' structure and logic (class diagrams, state charts, ...) and for generation of production-ready source code from them.
Features highlight
Code generation from UML class diagrams and state charts
- Several optimizing code generation algorithms
- Supports C, C++ and Python output language
- Available for MS Windows, Linux and Mac OS X
- Reverse source code engineering (full round-trip code engineering supported)
- Aimed to embedded software design
- Supports both blocking and non-blocking state charts
34- Object Graph Visualizer
35- Taylor MDA
Taylor MDA is a specialized UML modeling tool based on Eclipse. It uses convention-based techniques to generate the maximum code from streamlined UML models. Templates are included for generating JEE applications based on JPA/EJB3 and JSF/Seam/Facelets.
36- VisualPerspective
VisualPerspective is a free modeling and diagram creation tool. It enables to create free diagrams but also semantic oriented ones (for instance UML diagrams), in order to run automatic processing (transformations, exports, parsing).
Features
- UML Modeling
- Java code generation
- Free diagram modeling
- HTML code generation
- SQL Server datastructure import