PlantUML Editor

A free PlantUML browser editor designed for drawing with real-time live preview capabilities. Verify UML diagrams instantly as you type and save images easily. Works entirely in your browser, ensuring your diagram data is never sent to any external server.

Diagrams are rendered entirely in your browser using PlantUML WASM. Your diagram code is never sent to any external server. The PlantUML engine is downloaded once from CDN and cached by your browser.

Input

Type your PlantUML code here or drag & drop a .puml file...

Output

Initializing PlantUML Engine...

Failed to load CheerpJ runtime

First load takes 10-20 seconds. Subsequent visits will be much faster.

Guide & Terminology

What is the PlantUML Editor?

A real-time PlantUML editor with live preview. Write diagram code on the left and see the rendered result on the right — all processed entirely within your browser.

How to use

Select a template from the toolbar or write your own PlantUML code.
The diagram is rendered automatically as you type.
Use fullscreen mode for a distraction-free editing experience.
Click Download to save the rendered diagram as PNG.

Privacy

All processing happens in your browser via PlantUML WASM. No diagram data is ever sent to external servers.

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