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mermaid - Markdownish syntax for generating flowcharts, sequence diagrams, class diagrams, gantt charts and git graphs.

Mermaid lets you create diagrams and visualizations using text and code.
It is a Javascript based diagramming and charting tool that renders Markdown-inspired text definitions to create and modify diagrams dynamically.
The main purpose of Mermaid is to help with Visualizing Documentation, and helping it catch up with Development.
Diagramming and Documentation cost precious developer time and get outdated quickly. However, not having diagrams or documentation ruins productivity and hampers organizational learning.
Mermaid addresses this Catch-22 situation by reducing the time, effort and tooling that is required to create modifiable diagrams and charts which in turn results in smarter and more reusable content. Mermaid, as a text-based diagramming tool allows for quick and easy updates and makes documentation much easier. It can also be included in production scripts and other pieces of code as per requirement.
Even non-programmers can create diagrams through the Mermaid Live Editor, Visit the Tutorials Page for the Live Editor video tutorials.
Many editors, wikis and other tools also have mermaid integrations and plugins, making it easy to start using mermaid. A few of those are described in Simple start to write diagrams.
For a more detailed introduction to Mermaid and some of it's basic uses, refer to Overview for Beginners and Usage.
Mermaid was nominated and won the JS Open Source Awards (2019) in the category "The most exciting use of technology"!!!
Thanks to all involved, people committing pull requests, people answering questions and special thanks to Tyler Long who is helping me maintain the project 🙏
In depth guides and examples can be found at Getting Started and Usage.
It would also be helpful to learn more about mermaid's Syntax.
To select a version:
Replace with the desired version number.
To Deploy Mermaid:
  1. You will need to install node v16, which would have npm
  1. Download yarn using npm
  1. Enter the following command:
  1. You can then add mermaid as a dev dependency using this command:
To deploy mermaid without a bundler, one can insert a tag with an absolute address and a call into the HTML like so:
Doing so will command the mermaid parser to look for the tags with . From these tags mermaid will try to read the diagram/chart definitions and render them into svg charts.
Examples can be found at Other examples
Things are piling up and I have a hard time keeping up. It would be great if we could form a core team of developers to cooperate with the future development of mermaid.
As part of this team you would get write access to the repository and would represent the project when answering questions and issues.
Together we could continue the work with things like:
  • Adding more types of diagrams like mindmaps, ert diagrams, etc.
  • Improving existing diagrams
Don't hesitate to contact me if you want to get involved!
We use eslint. We recommend you to install editor plugins to get real time lint result.
Manual test in browser: open
For those who have the permission to do so:
Update version number in .
The above command generates files into the folder and publishes them to npmjs.org.
Many thanks to the d3 and dagre-d3 projects for providing the graphical layout and drawing libraries!
Thanks also to the js-sequence-diagram project for usage of the grammar for the sequence diagrams. Thanks to Jessica Peter for the inspiration and for the starting point of gantt rendering.
Mermaid was created by Knut Sveidqvist for easier documentation.
Here is the full list of the projects contributors.