Diagrams as text, powered by AI.

Write in Mermaid, PlantUML, D2 or DBML —or sketch freehand—, ask the AI for changes with your own API key, and keep everything in projects you can export, import and share.

Everything you need

• 4 diagram languages — Mermaid, PlantUML, D2 and DBML with configurable themes, styles and backgrounds.
• Freehand whiteboard — Hand-drawn sketches you can turn into Mermaid.
• AI with your API key — Five providers, a context-aware chat, fixes and conversion between languages.
• Projects & folders — VS Code-style explorer with drag and drop, search and shortcuts.
• Export & import — PNG, SVG, PDF, Markdown and whole projects as ZIP. No lock-in.
• Share with control — Links with access codes, expiration and copy-code permission.
• Serious security — MFA (TOTP app or email), Google sign-in, lockout after failed attempts and audit log.
• Spanish & English — Interface, emails and AI replies in your language.

Simple pricing

Every feature on every plan. Only the number of projects and diagrams changes.

FAQ

What is DiagramaHub?

A platform to create, organize and export diagrams written as text (Mermaid, PlantUML, D2 and DBML), plus a freehand whiteboard. It's available as Cloud (SaaS) or Self-host (on your infrastructure).

What's the difference between Cloud and Self-host?

Cloud is our ready-to-use SaaS at app.diagramahub.com. Self-host is the same open-source software installed on your infrastructure, with full control over data, plans and payments.

How does the AI work?

You connect your own API key from OpenAI, Anthropic, Google Gemini, DeepSeek or MiniMax and pick a model. From the chat you generate diagrams, explain, improve, fix or convert them to another language. The key is stored encrypted.

Does the AI cost extra?

Not with us. You use your own API key and pay your provider directly for what you use.

What can I export and import?

Export any diagram to PNG (1x, 2x or 3x), SVG, PDF or Markdown, and whole projects or folders to a ZIP or to a Markdown file that gives an AI context. Import .mmd, .puml, .d2, .dbml, Markdown, ZIP and Excalidraw files.

Are my diagrams locked into DiagramaHub?

No. Your diagrams are text: export a whole project at any time and take it to another tool or to your repository.

Can I share diagrams with others?

Yes. Create a public link or one protected with an access code, expiring in 5, 10 or 30 days or never, and decide whether recipients can copy the source code.

What security measures are in place?

MFA with a TOTP app or email plus recovery codes, Google sign-in, lockout after failed attempts, rate limiting, security headers and an audit log with 90-day retention. The code is continuously scanned with Snyk.

How easy is it to self-host?

One command installs and configures everything with Docker Compose. On first launch, a wizard guides you through the initial setup.

Can I customize plans when self-hosting?

Yes. Define your own plans, prices and limits, with Stripe built in and an architecture ready for other payment providers.

Is it production-ready?

DiagramaHub is in beta (v0.x) because it moves fast: we ship improvements almost every week. Some APIs and data structures may still change between versions, and every change is documented in the release notes. The security controls that already protect your account are listed in the Trust Center.

Does it support real-time collaboration?

Not yet; it's on our roadmap. Today you can share diagrams via links and exports.