Mermaid Viewer
A browser-based editor for Mermaid diagrams that renders your flowchart or architecture diagram as you type, with AI generation from a text description.
🔗 Visit Mermaid Viewer
Description
Mermaid is the text-based diagram syntax a lot of developers already use in README files and docs — you write a few lines describing boxes and arrows, and it renders a flowchart. Mermaid Viewer takes that syntax and wraps it in an actual editor: real-time preview as you type, an AI mode that generates the diagram from a plain-English description instead of hand-written syntax, and one-click export to SVG, PNG, PDF or JPG for dropping into docs or slides.
It's built for developers, architects and technical teams making governance workflows, timelines and design diagrams, with version history, annotations, shareable editor links, and syntax error detection. Data is stored locally for privacy, and there's a Docker-based enterprise option for self-hosting. Pricing: free for 3 diagrams, Starter at $69.99/year for 30 diagrams, and Pro at $119.99/year for unlimited diagrams and AI conversations.
💬 Our review
The short version: Mermaid Viewer is a decent, focused editor for a syntax most developers already touch, but the free tier's 3-diagram cap is stingy, and it's competing against genuinely free alternatives (the official Mermaid Live Editor, VS Code extensions) for a syntax that's open-source by design.
Against Lucidchart or Miro, which are heavyweight, general-purpose diagramming tools with steeper learning curves and higher prices, Mermaid Viewer is lighter and code-native — a better fit if your diagrams already live as Mermaid blocks in Markdown docs. Against PlantUML or Structurizr, which serve a similar code-as-diagram niche, its real edge is the AI generation from text and the polish of real-time preview plus multi-format export. The catch is that Mermaid itself is free and has a free official live editor; paying $70-120/year only makes sense if you specifically want the AI generation, version history, and export formats this product adds on top. Worth it for teams doing this daily who want a nicer workflow than raw syntax; skippable if you only render the odd diagram occasionally.
📊 Global score
🤖 AI-enriched data
Gratuit : 3 diagrammes. Starter $69.99/an (30 diagrammes). Pro $119.99/an (diagrammes illimités + conversations IA illimitées).
Pros
Aperçu temps réel pendant la saisie
Génération IA de diagrammes à partir d'une description texte
Export multi-format (SVG, PNG, PDF, JPG)
Option enterprise auto-hébergée via Docker
Cons
Palier gratuit limité à 3 diagrammes seulement
Concurrence face à l'éditeur Mermaid officiel gratuit
Abonnement annuel uniquement, pas d'option mensuelle affichée