Add a Diagram to a README

Create diagrams GitHub renders natively in your README.

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Diagram code

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💡 Write diagrams in Mermaid syntax — flowcharts, sequence diagrams, Gantt charts, class diagrams, and more — and export as SVG or PNG. Rendering happens entirely in your browser; nothing is uploaded.

GitHub tips

📖

GitHub renders Mermaid in Markdown — paste your code in a ```mermaid block and it shows inline.

🔧

Use this editor to get the syntax right with a live preview before committing.

🖼️

If you need an image instead, export SVG or PNG here.

🔒

Everything runs in your browser.

How It Works

Enter

Enter your data into the tool above. Everything stays local to your browser.

Process

The tool processes your data instantly in your browser using JavaScript. No server, no waiting.

Download

Get your result instantly. Nothing is stored after you leave the page — complete privacy.

Why use ours?

✓Completely free — no hidden costs, ever

✓No account, email, or login required

✓Files never leave your device

✓No file size limits whatsoever

✓No watermarks on any output

Also check out…

🔀

Make a Flowchart

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↔️

Draw a Sequence Diagram

Diagram how systems or people interact over time.

📆

Build a Gantt Chart

Lay out a project timeline as a Gantt chart from t

🧱

Create a Class Diagram

Diagram classes and their relationships for softwa

Frequently Asked Questions

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