Full Member Editor
Add attributes and methods with name, type, visibility (public, private, protected, package), and static or abstract flags — just like a real UML spec.
Chart & Visualization Tools
UML Class Diagram Maker
Create professional UML class diagrams with classes, attributes, methods, and relationships. Describe your system in plain language and let AI build the diagram for you.
Features
Everything You Need for UML Class Diagrams
From simple object models to complex domain architectures — all in one tool.
8 Relationship Types
Model inheritance, composition, aggregation, association, dependency, realization, and more with accurate UML arrow notations.
Class Stereotypes
Tag classes as Interface, Abstract, Enumeration, or Service to communicate design intent at a glance.
Cardinality Labels
Define multiplicity on each relationship end (1, 0..1, 1..*, *) so readers understand the exact object associations.
Zoom and Pan
Navigate large, complex class hierarchies smoothly with built-in zoom and pan controls — no clutter, just clarity.
AI-Powered Generation
Describe your domain model in plain English and get a complete UML class diagram with classes, members, and relationships in seconds.
Data input
Model Any Object-Oriented System
Type It In
Manually add classes, define their members, and wire up relationships using the intuitive editor.
Describe with AI
Write a plain-language description of your system and let AI generate the full class diagram instantly.
Paste Your Schema
Copy a list of classes and properties from your notes or docs and refine the structure in the editor.
Upload a File (Pro)
Import CSV or structured data files to bootstrap your class diagram from existing documentation.
Share
Share and Embed Anywhere
Download as PNG or SVG
Export crisp, high-resolution images for wikis, presentations, and technical documentation.
Share a Link
Generate a shareable URL so teammates can view or fork your class diagram instantly.
Embed in Your Site
Drop an embed code into Confluence, Notion, or any website to keep diagrams live alongside your docs.
Copy to Clipboard
Grab the diagram image in one click and paste it directly into Slack, Jira, or email.
About the UML Class Diagram Maker
MakeCharts built this tool so developers, architects, and educators can create clear UML class diagrams without fighting complex software. Describe your system or build it manually — either way, you get a professional diagram in minutes. It is free, browser-based, and designed to get out of your way.
<2 minDiagram ready in
8 typesRelationship types
4 levelsVisibility modifiers
5 optionsClass stereotypes
IncludedFree AI credits
Workflow
From Idea to Diagram in 3 Steps
Describe or Define Your Classes
Type a plain-language description of your domain model, or manually add classes and their members using the editor.
Configure Members and Relationships
Add typed attributes and methods with visibility modifiers. Connect classes using inheritance, composition, aggregation, or other UML relationship types.
Export and Share
Download your UML class diagram as a PNG or SVG, share a link with your team, or embed it directly in your technical documentation.
Use cases
Who Uses the UML Class Diagram Maker
Design Domain Models Before Coding
Map out your object-oriented architecture visually before writing a single line of code, catching design issues early.
Document Existing Systems
Reverse-document legacy codebases and living systems so new team members can understand the structure at a glance.
Teach Object-Oriented Principles
Create clear, annotated class diagrams to teach inheritance, encapsulation, polymorphism, and OOP design patterns.
Align Cross-Functional Teams on Data Models
Communicate the shape of your data and business logic to product managers, QA engineers, and stakeholders without a coding background.
Templates
Start with professionally designed templates
Classroom Management System Class Diagram Templateclassdiagram
Ready-to-use UML class diagram template for classroom management systems. Map teachers, students, courses, grades, and attendance visually. Free to edit.
Data Classification Framework Class Diagram TemplateclassdiagramVisualize your data classification framework with a UML class diagram. Map assets, access policies, retention rules, and audit trails in one view.
Object Oriented Design Template: UML Class DiagramclassdiagramFree OOP class diagram template with inheritance, interfaces, and relationships for a library management system. Customize and export instantly.
UML Class Diagram TemplateclassdiagramDesign clear UML class diagrams with this ready-to-use template. Visualize classes, attributes, methods, and relationships instantly. Free to use online.
Inheritance Hierarchy Class Diagram TemplateclassdiagramVisualize OOP inheritance with this UML class diagram template. Map abstract classes, subclasses, and overridden methods in minutes. Free and ready to use.
Related Tools
Create similar charts with these tools
Class Diagram Generatorclassdiagram
Generate UML class diagrams in seconds with AI. Add classes, members, stereotypes, and relationships from plain text. Free with SVG and PNG export.
Generate Class Diagrams FastclassdiagramGenerate a class diagram from source code with AI. Detect classes, members, and relationships; customize a classdiagram. Free: edit, zoom, export.
UML Class Diagram MakerclassdiagramDesign clean UML class diagrams online with our UML class diagram maker—free and AI‑powered. Add classes, members, stereotypes, relationships. Customize, zoom, and export or embed fast.
Class Diagram MakerclassdiagramBuild UML class diagrams instantly. Define classes, members, and relationships visually — no coding needed. Free class diagram maker powered by AI.
Comparison
MakeCharts vs. Traditional UML Tools
Heavyweight UML software was built for a different era. MakeCharts is built for speed.
MakeCharts UML Class Diagram Maker
- Fully browser-based — no download or install needed
- Intuitive editor with guided fields for classes and members
- Free tier available with all core UML class diagram features
- One-click PNG, SVG export and shareable links
- AI generates complete class diagrams from a plain description
- Clean, professional output ready for technical docs and presentations
Legacy UML Tools
- Install required — desktop apps with long setup times
- Steep learning curve with complex menus and notation rules
- Expensive licenses for full UML support
- Hard to share — proprietary file formats
- No AI assistance — every class and relationship drawn by hand
- Outdated exports that look low-quality in modern docs
FAQ
Frequently Asked Questions
What is a UML class diagram?
A UML class diagram is a structural diagram in the Unified Modeling Language (UML) that shows a system's classes, their attributes and methods, and the relationships between them. It is the most commonly used diagram in object-oriented software design and is used to model domain logic, document architecture, and plan code structure.
Is this UML class diagram maker really free?
Yes. You can create, customize, and download UML class diagrams completely free — no sign-up required. The free plan includes all core class diagram features: classes, members, relationships, and PNG export. AI-powered generation is also available free with limited credits on every account.
Can I generate a UML class diagram with AI?
Absolutely. Just describe your system or domain model in plain English — for example, 'a library system with Book, Author, and Member classes' — and the AI will generate a complete UML class diagram with attributes, methods, and appropriate relationships. You can then refine the result in the editor.
What relationship types does the UML class diagram maker support?
The tool supports all standard UML relationship types: Inheritance, Composition, Aggregation, Association, Dependency, Realization, Link, and Dashed Link. You can also add cardinality labels (like 1, 0..1, 1..*, *) and optional text labels to each relationship.
How do I add attributes and methods to a class?
Use the member editor inside each class. For each member you can set the name, type, visibility (public, private, protected, or package), and toggle whether it is a method, static, or abstract. Return types can also be specified for methods. The diagram updates instantly as you edit.
Can I use stereotypes like Interface or Abstract in my class diagram?
Yes. Each class can be tagged with a stereotype: Interface, Abstract, Enumeration, Service, or none. Stereotypes appear in the diagram using standard UML notation, making it easy to distinguish between concrete classes, interfaces, and enumerations at a glance.
What file formats can I export my class diagram to?
Free users can download their UML class diagram as a high-quality PNG — suitable for presentations, wikis, and documentation. Paid plans add SVG export for fully scalable, editable vector output. All plans support copying the diagram to clipboard and sharing via link.
Is the online UML class diagram maker suitable for complex architectures?
Yes. The tool supports zoom and pan navigation, making it easy to work with large diagrams containing many classes. You can add as many classes, members, and relationships as your model requires. For very large systems, the AI generator can scaffold the structure quickly, which you then refine.
Do I need to know UML notation to use this tool?
No prior UML knowledge is required. The editor guides you through adding classes, members, and relationships with plain-language labels. If you want AI to handle the notation entirely, just describe your system and the tool will apply the correct UML conventions automatically.
Can I embed my UML class diagram in Confluence or Notion?
Yes. Plus and Pro plan users can generate an embed code to insert live diagrams directly into Confluence, Notion, or any website that supports iframes. Alternatively, export as PNG or SVG and attach the image directly to any documentation tool.
Built for Every Team and Skill Level
- No UML expertise required — guided fields handle the notation for you
- Works in 12+ languages across the full interface
- Optimized for desktop and tablet — great on any screen size
- Accessible controls and high-contrast diagram output
- Suitable for students, developers, architects, and educators alike
- Start without an account — sign up only when you want to save your work
Your Diagrams, Your Data
- Your class diagram data is not sold to third parties
- Diagrams you create are yours — download or delete anytime
- You control what is shared and with whom
- No tracking beyond what is needed to run the service
- AI generation inputs are not used to train models without consent
- Account deletion removes your saved diagrams from our systems
Start now
Create Your UML Class Diagram Now
Free, instant, and no install required. Your object model is one description away.
- All UML relationship types included
- AI diagram generation from plain English
- PNG and SVG export
- No sign-up to start
- Shareable links for team collaboration
- Works in your browser on any device
No account needed. Your diagram is ready in seconds.