UML‑accurate notation
Generate correct class boxes, member visibility symbols, stereotypes, and relationship arrows that follow UML standards.
Chart & Visualization Tools
UML Class Diagram Maker
Create clear UML class diagrams in minutes. Define classes, members, visibilities, stereotypes, and relationships with instant preview.
Features
Why this class diagram tool
UML‑accurate, readable, and fast—powered by AI.
Smart auto‑layout
Avoid overlaps and tangled lines. The layout engine spaces classes and routes connectors for instant clarity.
Class & member editor
Quickly add properties and methods with type, visibility, static, and abstract flags—no clunky dialogs.
Rich relationships
Create inheritance, composition, aggregation, association, dependency, realization, and links with labels and cardinalities.
Readable styling
Set chart title and font size, and use consistent shapes for easy scanning and presentation‑ready output.
Zoom and pan
Explore large models smoothly with zoom/pan controls for focused reviews and demos.
Data input
Bring your structure
Type Classes
Enter class names, stereotypes, and members directly in the editor.
Paste Outline
Paste a simple text outline of classes and relationships to convert into UML.
Use AI Prompt
Describe your system; AI proposes classes, members, and relationships instantly.
Import Spec (Pro)
Upload a simple spec (Pro) to prefill classes and relationships.
Share
Share and export
Download SVG/PNG
Export crisp diagrams for docs, slides, or repos.
Share Link
Send a view link with your latest changes.
Embed Anywhere
Embed the diagram in your wiki or site.
Version Save
Save and update diagrams without rebuilding (Starter+).
About this tool
This AI‑powered maker builds UML class diagrams fast. It focuses on clear notation, readable layout, and easy editing. Start free, no sign‑up required. When ready, save, share, and embed. Ideal for students, developers, and architects.
<2 minTime to first diagram
7Relationship types
Mobile to desktopWorks on any device
12+Languages supported
Workflow
How it works
Describe or start
Type a prompt like what classes you need, or begin with the preview and build from there.
Edit classes
Use the class editor to add members, types, visibility, static/abstract, and optional stereotypes.
Connect relationships
Add inheritance, composition, aggregation, association, dependency, or realization and specify labels/cardinalities.
Tweak and export
Set chart title and font size, enable zoom/pan, then download SVG/PNG or embed a live link.
Use cases
Use cases
Model domains and APIs
Sketch entities, services, and boundaries to align teams before coding.
Teach UML concepts
Demonstrate inheritance, composition, and interfaces with clean visuals.
Communicate options
Compare alternative designs and document decisions for stakeholders.
Document services and DTOs
Map service contracts, persistence models, and dependencies clearly.
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.
Class Diagram MakerclassdiagramBuild UML class diagrams instantly. Define classes, members, and relationships visually — no coding needed. Free class diagram maker powered by AI.
Domain Model Diagram MakerclassdiagramBuild domain model diagrams instantly with AI. Define classes, members, and relationships visually. Export as PNG or SVG for docs, presentations, and more.
Comparison
Why choose AI over manual
Less fiddling, more clarity.
AI‑assisted maker
- No setup—start free in browser
- Describe your system to generate UML fast
- Auto‑layout and tidy routing by default
- Edit once; regenerate and keep context
- One‑click export and simple embeds
- Affordable plans that scale with you
Manual UML tools
- Complex setup and dense menus
- Steep learning curve for basic tasks
- Rigid layouts that need constant tweaking
- Hard to keep models updated
- Export and embed are tedious
- Often costly or locked to devices
FAQ
Frequently asked questions
Is this a free UML class diagram maker?
Yes. You can create, customize, and export UML class diagrams for free. Upgrade only if you want extras like saving versions, embedding, or file uploads.
How does the AI UML class diagram generator work?
Describe the system you have in mind. The AI proposes classes, members, visibilities, stereotypes, and relationships. You can accept, edit, or regenerate parts while the preview updates instantly.
Can I model inheritance, composition, and aggregation?
Absolutely. Choose the relationship type and add labels and cardinalities like 1, 0..1, or 1..*. The diagram uses correct UML arrows and diamonds.
How do I add methods, properties, and visibility?
Open the class editor, add a member, set its type, mark it as method if needed, and pick visibility (public, private, protected, package). You can also mark members static or abstract.
Does it support stereotypes and interfaces?
Yes. Add stereotypes such as «interface», «abstract», «enumeration», or «service». Interface methods and abstract classes display correctly in the diagram.
How do I export or embed my diagram?
Download PNG or SVG for crisp visuals, or share a link to embed in your wiki or site. Your audience always sees the latest version.
Is there an online UML class diagram tool without signup?
Yes. You can start in the browser with no sign‑up. When you need saving and collaboration, sign in to unlock Starter or Pro features.
Can I collaborate or save versions?
Starter and Pro plans let you save, update, and reuse diagrams. Share links for reviews and keep a single source of truth.
What makes this better than traditional UML software?
AI speeds up modeling with natural language and auto‑layout. The interface stays focused on UML essentials, exports are instant, and you avoid heavy installs or expensive licenses.
Is this really a UML class diagram maker free of charge?
Yes—core features are free, including the online builder and exports. Upgrade only if you need advanced options like file uploads or priority support.
Inclusive by design
- Keyboard‑friendly navigation and editing
- Readable defaults with adjustable font size
- Zoom and pan for low‑vision accessibility
- Color choices designed for contrast clarity
- Responsive layout for mobile, tablet, and desktop
Your privacy, respected
- Your diagrams are private until you share a link
- We never sell your data or diagram content
- Export anytime—no lock‑in with PNG/SVG
- Delete diagrams or your account whenever you choose
- All traffic is encrypted in transit
Start now
Build your UML now
Start free, describe your system, and get a clean class diagram in minutes.
- AI‑assisted generation
- UML‑accurate relationships
- Readable auto‑layout
- SVG/PNG export and embed
- Zoom and font controls
Tip: include stereotypes, visibility, and cardinalities (e.g., 1..*, 0..1).