View, edit, and export Mermaid diagrams. Import from URL or file, choose themes, toggle fullscreen, and download as PNG or SVG.
URL Import
Fetch diagrams from GitHub, Gists, or any URL
File Upload
Drag & drop .md, .mmd, or .txt files
Export Options
Download as high-res PNG or clean SVG
Theme Switcher
Dark, light, forest, and neutral themes
Mermaid lets you create diagrams and visualizations using a simple text-based syntax. It's widely used in documentation, READMEs, and technical specifications because diagrams can be version-controlled alongside code.
Popular uses include architecture diagrams, API documentation, incident timelines, and process flows. GitHub, GitLab, and Notion all support Mermaid syntax natively.
Mermaid is a JavaScript-based diagramming and charting tool that uses text and code to render diagrams. It supports flowcharts, sequence diagrams, pie charts, class diagrams, and more.
Mermaid supports flowcharts, sequence diagrams, class diagrams, state diagrams, entity-relationship diagrams, Gantt charts, Git graphs, user journey diagrams, and pie charts.
Yes! You can export your diagrams as high-resolution PNG (2x for retina displays) or as scalable SVG vectors. Both options are free and work entirely in your browser.
You can paste a URL to a .md file on GitHub or elsewhere, upload a file directly, or type/paste Mermaid code manually. The tool auto-detects mermaid code blocks in markdown files.
The diagram rendering happens entirely in your browser using the Mermaid.js library. Only URL fetching (to bypass CORS) goes through our servers temporarily.
You can choose between Default, Dark, Forest, and Neutral themes. Your preference is saved in your browser for future visits.
Start with keywords like flowchart, sequenceDiagram, or classDiagram.
Use simple text syntax. For example: A --> B creates an arrow from A to B.
See your diagram update instantly as you type. Use themes to switch between light and dark modes.
Download as PNG for presentations or SVG for scalable graphics. Perfect for documentation and GitHub READMEs.
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