merMDitor
A simple Markdown editor with Mermaid diagram support
Write Markdown, see it rendered instantly, and add diagrams with Mermaid syntax. No signup required, works in your browser, saves automatically to local storage.
What it does
Markdown editing
Standard Markdown with GitHub flavor support. Includes syntax highlighting, keyboard shortcuts, and formatting buttons.
Mermaid diagrams
Create flowcharts, sequence diagrams, and other visuals using Mermaid syntax. Renders in real-time as you type.
Live preview
Split-pane view with instant preview. See exactly how your markdown will look while you write.
Auto-save
Your work is automatically saved to browser local storage. No accounts, no data sent anywhere.
Free to use
No registration, no payments, no limits. Just open it and start writing.
Built-in help
Quick reference for Markdown and Mermaid syntax available when you need it.
Good for
Documentation
API docs, project READMEs, technical guides. Add flowcharts and architecture diagrams inline with your text.
Note-taking
Meeting notes, research, study materials. Organize thoughts with headers, lists, and visual diagrams.
Planning & Design
System design, process flows, database schemas. Sketch ideas quickly with Mermaid diagrams.