If you’ve ever tried to hand-write Mermaid.js syntax for a flowchart, you know the frustration: one misplaced arrow and the whole diagram breaks. Mermaid Flow flips that around — draw your diagram visually and it generates clean Mermaid code you can drop straight into a GitHub README. As someone who keeps architecture diagrams in version control, I had to try it. Here’s my honest review.
Mermaid Flow (mermaidflow.app) is an online visual Mermaid live editor. It lets you create and maintain Mermaid.js diagrams by dragging and dropping nodes, edges and labels — then it generates the underlying Mermaid JS code, which renders directly in GitHub READMEs and can be stored and version-controlled like any other code. So you get the stability of version-controlled diagrams with the simplicity of just drawing. It’s also AI-powered: describe the diagram you want and it generates it in seconds. It’s used by 67,000+ people.
If you keep diagrams in your repo, Mermaid Flow gives you visual editing plus version-controllable Mermaid code — the best of both worlds.
If your docs lag behind your code, text-based diagrams that live next to the code are far easier to keep current.
If you like Mermaid’s output but not hand-coding it, the drag-and-drop editor removes the syntax headaches.
Visual editing currently focuses on flowcharts (more types are planned), so if you need visual sequence/class diagrams right now, check current support.
If you want freeform graphics rather than Mermaid-compatible diagrams, a tool like Figma or draw.io fits better.
Build flowcharts by dragging nodes, edges and labels — no need to memorize Mermaid syntax — while the app keeps the underlying code in sync.
Every diagram outputs Mermaid JS code you can render in GitHub READMEs and commit to your repo, so diagrams stay in sync with development.
Powered by an advanced GPT model, the AI agent lets you describe a diagram in plain language and generate it instantly, or chat to modify and repair existing diagrams.
Premium adds unlimited saved diagrams, high-quality image exports, commercial use rights and an ad-free experience with priority support.
Mermaid Flow has a Free plan for hobbyists (visual editor) and a Premium plan at $7.75/month billed annually ($92.99/year), or $10/month monthly. Premium unlocks unlimited saved diagrams, high-quality exports, commercial use, the full AI agent, ad-free use and priority support. Pricing can change, so confirm current rates on the site, but the free tier lets you try the visual editor first.
Pros: Visual editing that outputs real, version-controllable Mermaid code; renders in GitHub READMEs; AI agent to generate and repair diagrams; high-quality exports; affordable Premium ($7.75/mo annual); free tier; large user base.
Cons: Visual editing currently centers on flowcharts (more types planned); AI features and unlimited saves require Premium; it’s Mermaid-specific, not a general design tool; some features still listed as “coming soon.”
The official Mermaid Live Editor is free but code-first — you type Mermaid syntax and see it render. Mermaid Flow adds a true visual drag-and-drop layer plus an AI agent on top of that workflow, so you can build diagrams without writing syntax and still get clean, committable code. If you’re happy hand-writing Mermaid, the official editor suffices; if you want speed and visual editing, Mermaid Flow is the upgrade.
For developers and technical writers who rely on Mermaid diagrams, Mermaid Flow is a genuinely useful tool in 2026 — it removes the syntax pain while preserving version-controlled, GitHub-ready output, and the AI agent speeds things up further. The visual editor’s flowchart focus is the main limitation, but at $7.75/month for Premium (with a free tier to start), it’s an easy recommendation for anyone who diagrams in code.
It’s an online visual editor for Mermaid.js diagrams that lets you drag and drop to build flowcharts and generates committable Mermaid code.
Yes — the generated Mermaid code renders directly in GitHub README files and can be version-controlled.
Yes, a free plan with the visual editor; Premium is $7.75/month billed annually (or $10 monthly).
Yes — an AI agent (powered by an advanced GPT model) generates, modifies and repairs diagrams from plain-language descriptions.
Visual editing focuses on flowcharts today, with more types planned; all Mermaid types are supported via text and AI editing.
You can start creating diagrams free here: Try Mermaid Flow →
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