Beauty Diagram — Mermaid Online Live Editor with Beautify & Export

Re-layout for flowcharts

Mermaid, PlantUML, and draw.io flowcharts get re-laid out on a grid with orthogonal routing — no diagonal arrows cutting through nodes.

9 themes you can swap

Switch between modern, atelier, atlas, obsidian, and more without editing the source. The same Mermaid renders for a deck, a doc, or a dark-mode README.

Editorial-grade typography

Geist at 14px / 500 with OpenType ligatures and baseline-aligned labels. The diagram looks like a slide, not a wiki page.

AI generate / refine

Describe what you want in plain English — AI drafts the Mermaid or PlantUML source, then refine an existing diagram with the same loop. No prompt engineering required.

Embed straight into READMEs

Drop a Beauty Diagram image URL into any markdown (GitHub, Notion, Medium) — the rendered SVG loads on every view. No save, no re-export when you tweak the source.

5 animated SVG styles

Layer subtle, lightning, laser, charge, or pulse motion onto the same Mermaid source. Clarifies sequence and direction without rewriting the diagram.

How do I beautify a Mermaid flowchart?

Paste your Mermaid source into the editor. Beauty Diagram re-lays it out with orthogonal routing, applies a sleek, modern palette, and exports SVG in under 400ms. You keep the original code; only the render changes.

How do I improve a PlantUML activity diagram?

Same flow — swap the tab to PlantUML, paste, click Beautify. The diagram formatter realigns swimlanes, normalizes node sizes, and fixes the cramped default spacing that PlantUML ships with.

Mermaid vs PlantUML — which should I use?

Mermaid is easier to read in Markdown and has wider native support (GitHub, Notion). PlantUML is more expressive for UML — class, sequence, state, activity. Beauty Diagram supports both, so pick whichever your source tree already uses.

Can I import a draw.io file?

Yes — free, no signup needed. Drop a .drawio or .xml export into the editor — compressed or uncompressed both work — and we convert flowcharts, sequence diagrams, class and entity-relationship diagrams, mindmaps, and git branching diagrams into Mermaid source, then beautify from there. An optional AI-enhance toggle for messier diagrams is included with Pro and Premium, or payable per use from a credit pack. You stay in the Mermaid workflow after import, with the original file untouched.

SVG vs PNG for diagrams — which export format?

SVG for anything that will be viewed on screen (docs, websites, Figma embeds) — it stays crisp at any zoom. PNG for decks that will be exported to PDF or printed, or when the destination tool does not support SVG. Beauty Diagram exports 4× PNG on Pro — no watermark.

Can I export Mermaid to SVG or PNG without rendering manually?

Yes. Every beautified diagram gets a one-click export to both SVG and PNG. No CLI, no puppeteer, no Node dependency to install.

Is this just a Mermaid Live editor clone?

No. The Mermaid live editor renders what Mermaid gives you. Beauty Diagram post-processes that render — re-layout, spacing, typography, palette — so the result is something you would actually paste into a deck.

Can I tweak colors without editing the source code?

Yes. Click any node or line on the canvas and a floating toolbar appears — change background, border, line color, width, and text color with one tap. Your source stays untouched; the customizations save with the diagram and travel with the shared link.

Works with the formats you already write →

MERMAIDPLANTUMLDRAWIOSVG

Renders inside the tools you already use →