# Mermaid Diagram

> Render Mermaid diagrams from text: flowcharts, sequence diagrams, ER charts, and more. Paste DSL, preview the graph, and copy the source for docs. Rendering is client-side so architecture sketches do not leave your machine.

Runs in your browser. Nothing is uploaded.

[Web](https://toolbuddy.dev/categories/web.md)

## About this tool

Render Mermaid flowcharts, sequence diagrams, and other DSL in the browser. The mermaid library is lazy-loaded with next/dynamic and ssr: false, then diagrams re-render on a short debounce as you type. A loading state appears until the library is ready.

How to use: start from a flowchart or sequence template, edit the source, wait for the SVG preview. Copy the source for docs. Invalid DSL shows an error instead of a blank canvas.

Example: a three-node flowchart is enough for a README architecture sketch. Sequence diagrams help API call order. This is not a full diagram SaaS with collaboration or export to every vendor format.

Architecture sketches are not uploaded to a diagram host. Rendering uses client-side mermaid only. After the library loads once, you can keep editing offline. Keep diagrams short for readability; huge graphs may be slow in the tab. Copy source into a README rather than screenshotting if you can. If you need to convert a screenshot, try [Online Image Converter](https://onlineimageconverter.net/). If you need the diagram in a PDF, try [LoveThisPDF](https://lovethispdf.com/).

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