Here, we compiled a list of the 11 best websites to draw UML class diagrams online. UML stands for Unified Modeling Language, and software engineers use it to conceptualize and design object-oriented software architecture.
A class diagram is a structural UML diagram that showcases a software system’s various classes, attributes, methods, and relationships among its objects.
Class diagrams in UML are widely popular as they provide a high-level abstraction view of the software system.
It can become an effective communication tool for developers to convey their ideas to stakeholders without digging deep into the source code.
Also Read: 10 Best Free Websites To Draw Activity Diagrams Online
Top 11 Class Diagram Maker Tools for UML Design (Free)
This article will explore the five best online websites to draw UML class diagrams. These online diagramming tools will make your job easier as they consist of pretty templates you can edit to draw a class diagram with minimum effort.
Most offer intuitive and modern drag-and-drop functionalities, making your life easier if you want to draw a class diagram from scratch.
Let’s now see these online class diagram tools:
1. Creately
Creately is one of the best online diagramming and collaboration tools for drawing UML class diagrams online.
The best part is that it offers multiple frameworks for displaying a system’s structure.
It offers a modern interface that lets you drag and drop various elements to design a class diagram.
Creately Features:
- Drag and drop interface
- It supports most shapes and elements to draw class diagrams
- Real-time collaboration via video conferencing
- Pre-defined templates to design classes and other UML diagrams
- Panel to take quick notes
- Supports keyboard shortcuts
- Share your class diagrams with your teammates or other stakeholders
- Add comments
- Supports integration with third-party cloud apps such as Google, Microsoft, Salesforce, Slack, and many other productivity tools
- Export the class diagram in JPG, PNG, SVG, or PDF format
Pricing: Free plan with 3 canvases (60 items max) and limited storage.
Try this tool to draw class diagrams online here.
2. Mockplus RP
Mockplus RP is an online flow diagramming and wireframing tool that allows designers to quickly present the design process and identify the process or the workflow you and your team want to document or visualize.
Mockplus Features:
- UI flow diagramming is as easy as drag-and-drop
- It supports most shapes for drawing class diagrams
- Real-time collaboration with teams
- Collect contextual feedback
- Keep everyone up-to-date
- Share and test early on
Pricing: A free plan is available to individuals.
Try Mockplus RP to draw wireframes online here.
Suggested Read: Top 60 Coding Quotes to Inspire Software Developers
3. Diagrams.net
Diagrams.net or Draw.io is a free online tool for drawing various engineering and business diagrams, including UML diagrams such as class and activity diagrams. Visit the link provided below to create a new diagram.
Afterward, as shown in the screenshot above, you can select a class diagram from the options dialog box to access its diagramming editor.
On the left-hand side is a toolbar with all the basic shapes needed to draw a class diagram. You can drag and drop different shapes from this toolbar to the main editing interface.
Once done, you can increase or decrease the shape’s size and connect them. You can also insert text and customize appearance options by making the font bold, changing color, etc.
After designing your class diagram, you can export it in multiple file formats such as JPG, PNG, SVG, PDF, HTML, XML, etc. The best part is that you can export class diagrams with a transparent background.
Diagrams.net Features:
- Works with Google Drive and Google Workspace
- Supports integration with OneDrive and SharePoint
- Offline support with a desktop app and VS Code plugin
- Embed and edit diagrams directly with the draw.io for the Notion Chrome extension
Try this tool to draw class diagrams online here.
Also Read: 9 Best Free Online YAML Editor Websites
4. Lucidchart
Lucidchart Features:
- Quickly style the shapes of your class diagram
- Supports keyboard shortcuts to work faster
- Expand your diagram canvas
- Organize class diagrams with containers
- Multiple support layers let you add all the little details in your class diagram.
- Collaborate with your team members
- Presentation mode
- Make your diagram publicly available via URLs
Pricing: Free plan available with 3 editable documents and 100 professional templates
Try this tool to draw class diagrams online here.
5. yUML
yUML is another of the best free online tools for drawing class diagrams. Apart from class diagrams, you can also use yUML to draw use cases and activity diagrams. The best part is that you don’t need to create an account to draw diagrams.
Visit the link provided below and click on the Draw UML Diagram button. This will take you to its diagramming interface, where you can write the yUML code to create class diagrams. Once done, you can export it as a PNG, JPG, SVG, or PDF file.
yUML Features:
- VS Code extension that lets you draw class diagrams and other UML diagrams based on the yUML syntax
- Create diagrams simply by typing plain text
- Use CI Scripts to draw UML diagrams
- Easily share class diagrams with others and embed them in Slack, Wiki, and blogs
Pricing: Free plan available with 5 saved diagrams
Try this tool to draw class diagrams online here.
6. Visual Paradigm Online
Visual Paradigm Online Features:
- Real-time collaboration
- More than 2000 templates
- 200+ diagram types
- Drag and drop interface to draw class diagrams
- Precise shape positioning with alignment guide
- Free for educational use
- Embed diagrams in MS documents and presentations
- Download class diagrams as JPG, PNG, or PDF files
Some of the pre-defined templates for class diagrams:
- Student’s enrollment class diagram
- ATM system class diagram
- Class Diagram Example: A Star-Based LAN
- Article Manager Class Diagram
- Order and Payment Class Diagram
Pricing: Free plan with basic templates, diagram symbols, charts, and stock photos.
Try this tool to draw class diagrams online here.
7. Gleek
Gleek Features:
- Create class diagrams and other UML diagrams without using your mouse
- Supports rapid diagramming via keyboard
- Live collaboration and version control
- Export class diagrams
- Pre-designed class diagram templates for common scenarios
- Customize the appearance of your diagram
Templates for class diagrams that you can use:
- Order processing system
- Animal inheritance system
- Movie enumeration example
- Library management system
- Restaurant management system
- Online shopping management system
Pricing: Free with 5 diagrams, 40 diagram objects, and only export as a PNG file.
Try this tool to draw class diagrams online here.
8. Moqups
Moqups Features:
- Drag and drop interface to draw UML diagrams such as class, object, component, etc.
- Built-in library with thousands of popular icon sets.
- Upload your images to use from your computer or cloud storage services.
- Prototype interactions and flow diagram.
- Real-time collaboration and comments.
- Easy link sharing and export to Google Drive or Dropbox.
- Export class diagrams as PDF and PNG files.
Pricing: Free plan available with 2 projects and 400 objects.
Try this tool to draw class diagrams online here.
9. Cacoo
Cacoo Features:
- Top-notch real-time collaboration with track changes features and brainstorming ideas with comments, video chat, and screen sharing.
- A diverse library of templates and shapes
- Import your images to refine your class diagrams
- Presentation mode to coherently share your ideas
- Share class diagrams with a link
- Export class diagrams as JPG, PDF, and other file formats
- Option to embed diagrams on websites
- In-app video and chat
- Supports dynamic charts and commenting
- Integration with Google Drive, Adobe Creative Cloud, and Confluence
Pricing: Free plan available
Try this tool to draw class diagrams online here.
Also Read: 60 Best Software Engineer Quotes for Developers and Coders
10. Sketchboard
Sketchboard Features:
- Simplifying team presentations and meetings
- Board password sharing
- Supports comments and integration with Slack
- Add shapes and images
- Modifying text with markdown text formatting
- Keyboard shortcuts support efficient diagramming
Note: In its free plan, a watermark is added to the exported class diagrams
Pricing: Free plan available with 5 users and 3 boards
Try this tool to draw class diagrams online here.
11. Miro
Miro Features:
- Design class diagrams with a modern editing interface to explain complex processes
- Real-time collaboration
- Infinite canvas
- Supports integration with JIRA, Slack, Google Suite, and many other SaaS-based productivity tools.
- Enterprise-grade security
- Easy and fast diagram creation
Pricing: Free plan available with 3 editable boards and core integrations
Try this tool to draw class diagrams online here.
Wrapping Up
This blog explored the 10 best free online tools for drawing UML diagrams. Using these free diagramming tools, you can quickly design visually appealing class diagrams and export them as JPG, PDF, or any other file format to share with different stakeholders.
The best part is that most of these online diagramming tools offer real-time collaboration features with in-app video conferencing, screen sharing, and chat. This allows you to streamline work with remote teams and enhance their brainstorming processes to design class diagrams effectively.
