Add a Diagram to a README

Create diagrams GitHub renders natively in your README.

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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.

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

Proses

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

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

Pam defnyddio ein un ni?

✓Hollol rhad ac am ddim - dim costau cudd, byth

✓Nid oes angen cyfrif, e-bost na mewngofnodi

✓Nid yw ffeiliau byth yn gadael eich dyfais

✓Dim cyfyngiadau maint ffeil o gwbl

✓Dim dyfrnodau ar unrhyw allbwn

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🔀

Make a Flowchart

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↔️

Draw a Sequence Diagram

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📆

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

Cwestiynau Cyffredin

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