Supported Diagram Types
| Diagram Type | Starts With | Common Use |
|---|
| Flowchart | flowchart TD | Processes, decisions, logic flow |
| Sequence | sequenceDiagram | Interactions between actors/systems |
| Class | classDiagram | OOP structure, relationships |
| State | stateDiagram-v2 | State machines, transitions |
| ER Diagram | erDiagram | Database entity relationships |
| Gantt | gantt | Project timelines and schedules |
| Pie Chart | pie | Proportional data |
| Mindmap | mindmap | Hierarchical ideas/notes |
Free Mermaid Live Editor
The Mermaid Live Editor is a free browser-based tool that lets you write
Mermaid Markdown and instantly generate professional diagrams with a live preview.
Whether you're documenting software architecture, planning workflows, creating UML diagrams,
or preparing technical documentation, this editor provides everything you need in one place.
Your Mermaid code is rendered in real time as you type, making it easy to experiment,
debug syntax, and build complex diagrams without installing any software.
Everything runs locally in your browser, keeping your work fast and private.
Supported Diagram Types
Create a wide variety of diagrams using Mermaid syntax, including:
- Flowcharts
- Sequence Diagrams
- Class Diagrams
- State Diagrams
- Entity Relationship (ER) Diagrams
- Gantt Charts
- Pie Charts
- Mind Maps
- Journey Diagrams
- Git Graphs
- User Journey Maps
- Requirement Diagrams
Key Features
- Instant live preview while editing.
- Supports multiple Mermaid diagram types.
- Syntax highlighting and easy editing.
- Copy Mermaid source with one click.
- Download diagrams as SVG.
- Export diagrams as PNG.
- Dark and light preview themes.
- Runs entirely inside your browser.
- No account or registration required.
- Works on desktop, tablet, and mobile devices.
How to Use the Mermaid Live Editor
- Choose a diagram template or start from scratch.
- Write or paste your Mermaid Markdown.
- Watch the live preview update automatically.
- Fix any syntax errors if needed.
- Copy the Mermaid code.
- Download the generated diagram as SVG or PNG.
Why Use Mermaid?
Mermaid allows developers, engineers, analysts, and technical writers to create diagrams
using simple text instead of drawing shapes manually. Since diagrams are stored as plain text,
they work well with Git, Markdown documentation, documentation generators, and CI/CD workflows.
Who Can Use This Tool?
- Software Developers
- Backend Engineers
- Frontend Developers
- DevOps Engineers
- Cloud Architects
- Technical Writers
- System Designers
- Business Analysts
- Students
- Teachers and Trainers
- Project Managers
Common Use Cases
- Software architecture documentation.
- API request and response flow diagrams.
- Database ER diagrams.
- Application state machines.
- Project timelines using Gantt charts.
- Git workflow visualization.
- Technical documentation in Markdown.
- Planning system workflows.
- Knowledge mapping with mind maps.
- Business process documentation.
Why Use This Mermaid Live Editor?
- 100% free to use.
- No installation required.
- Instant diagram rendering.
- Export high-quality SVG and PNG files.
- Supports modern Mermaid syntax.
- Fast and responsive interface.
- Works completely offline after loading.
- Your Mermaid code stays in your browser.
Start Creating Mermaid Diagrams
Write Mermaid Markdown, preview diagrams instantly, and export professional-quality
flowcharts, sequence diagrams, ER diagrams, Gantt charts, class diagrams, and more—
all from your browser with this fast, free Mermaid Live Editor.
Mermaid Syntax Basics
Mermaid diagrams are created using plain text instead of drawing shapes manually.
Each diagram starts with a keyword that defines its type, followed by the elements
and relationships you want to display. Because Mermaid files are text-based, they
can be stored in Git repositories, edited with any code editor, and version-controlled
alongside your project documentation.
| Diagram |
Starting Syntax |
| Flowchart |
flowchart TD |
| Sequence Diagram |
sequenceDiagram |
| Class Diagram |
classDiagram |
| ER Diagram |
erDiagram |
| State Diagram |
stateDiagram-v2 |
| Gantt Chart |
gantt |
Benefits of Using Mermaid Diagrams
- Create diagrams using simple text.
- Easy to maintain in Git repositories.
- Works perfectly inside Markdown documentation.
- Ideal for technical documentation and software architecture.
- Easy collaboration between developers and teams.
- No manual drawing required.
- Quickly update diagrams whenever requirements change.
- Supports modern documentation workflows.
Tips for Writing Better Mermaid Diagrams
- Use meaningful node names.
- Keep diagrams focused on a single topic.
- Avoid crossing lines whenever possible.
- Split very large diagrams into smaller sections.
- Use subgraphs to organize related components.
- Validate your syntax before exporting.
- Prefer SVG exports for documentation.
- Store Mermaid code with your project source.
Mermaid Editor vs Drawing Tools
| Mermaid Editor |
Traditional Drawing Software |
| Text-based diagrams |
Manual drag-and-drop editing |
| Version control friendly |
Binary project files |
| Easy collaboration |
Harder to merge changes |
| Quick updates |
Requires manual redesign |
| Developer focused |
Designer focused |
Browser Privacy
This Mermaid Live Editor performs parsing and rendering directly inside your browser.
Your Mermaid code is never uploaded to our servers, making it suitable for internal
architecture diagrams, confidential workflows, API documentation, and private project
planning.
Related Developer Tools
Frequently Asked Questions
What is Mermaid?
Mermaid is a text-based diagramming language that lets you create flowcharts, sequence diagrams, class diagrams, Gantt charts, ER diagrams, and other visualizations using simple Markdown-like syntax. Instead of drawing shapes manually, you write text that is automatically rendered into diagrams.
Which diagram types are supported?
This editor supports many Mermaid diagram types, including Flowcharts, Sequence Diagrams, Class Diagrams, State Diagrams, Entity Relationship (ER) Diagrams, Gantt Charts, Pie Charts, Mind Maps, Journey Diagrams, Git Graphs, Requirement Diagrams, and other Mermaid-supported formats.
Does this editor work offline?
Yes. After the editor and Mermaid library have loaded in your browser, you can continue creating and editing diagrams without an internet connection in most cases. Browser support and caching behavior may vary.
Can I export diagrams as SVG?
Yes. You can export your diagrams as SVG files, which are scalable vector graphics that remain sharp at any size and are ideal for websites, documentation, and presentations.
Can I export diagrams as PNG?
Yes. The editor allows you to download diagrams as PNG images, making them easy to share in documents, slides, reports, emails, and social media.
Is my Mermaid code uploaded to a server?
No. Your Mermaid code is processed entirely within your browser. Nothing is uploaded, stored, or shared with any server, helping keep your diagrams and documentation private.
Does this editor support GitHub Mermaid syntax?
Yes. The editor supports standard Mermaid syntax that is commonly used in GitHub Markdown and many documentation platforms. Some platform-specific features may depend on the Mermaid version being used.
Why is my diagram showing a syntax error?
Syntax errors usually occur because of missing keywords, incorrect indentation, invalid connections, unsupported diagram syntax, or typing mistakes. Review the highlighted error message, verify your Mermaid syntax, and ensure the diagram starts with the correct declaration such as flowchart TD or sequenceDiagram.
Can I use Mermaid in Markdown files?
Yes. Mermaid diagrams can be embedded in Markdown files using Mermaid code blocks. Many documentation platforms, including GitHub, GitLab, Obsidian, Docusaurus, MkDocs, and other supported tools, can render Mermaid diagrams automatically.
Is this Mermaid Live Editor free?
Yes. This Mermaid Live Editor is completely free to use. You can create, edit, preview, and export diagrams without creating an account or paying any subscription fees.