New: Markdown Mode Now Available

The Fully Private Mermaid and Markdown Viewer Your Mac Deserves

Looking for a clean, simple Mac app to write and preview Mermaid diagrams and Markdown — fully offline, completely private, with built-in history? Need to zoom, pan, and go fullscreen like a whiteboard for your meeting? That's exactly why we built this.

Download See Features

Mermaid diagram editor with live preview on Mac

Live Preview, Instant Feedback

Write Mermaid and Markdown code on the left, see your diagram render in real time on the right. Support for 20+ diagram types including flowcharts, sequence diagrams, Gantt charts, mind maps, ER diagrams, and more.

Mermaid + Markdown, One Editor

Switch to Markdown mode to write technical documentation with embedded Mermaid diagrams. Perfect for README files, design docs, and project wikis — all in one native app.

Meeting Presentation Powerhouse

Charts support free pan and zoom — zoom into specific details during meetings to walk your team through the data. No need for screenshots or slide decks. Just open the App and it becomes your whiteboard.

Everything You Need

Packed with thoughtful features for your daily workflow.

Smart History

Auto-saves up to 100,000 edit histories. Rename, favorite, and quick-switch between diagrams effortlessly.

Favorites

Mark your most-used diagrams for instant access. Never lose track of important work again.

4x PNG Export

One-click export at 4x resolution for crisp, print-ready diagrams. Perfect for presentations and documentation.

Fully Offline

Built-in Mermaid engine with zero internet dependency. Your data stays on your Mac, always private and secure.

Meeting Mode

Free pan and zoom on any diagram. Use it as a whiteboard during meetings — no extra slides needed.

Dark & Light Mode

Switch between dark and light themes to match your preference or time of day. Easy on the eyes, always.

What's New

We ship improvements constantly. Here are the latest updates.

v1.2 (3)

UI Polish & Quality-of-Life Improvements (In Apple Review)

Collapsible sidebar for a cleaner workspace. Scalable font size in Markdown preview for meeting-ready presentations. New always-on-top window mode.

v1.1 (2)

Markdown Support

Not just Mermaid anymore — switch to Markdown mode, which also supports embedded Mermaid diagrams for dual-mode viewing.

v1.0 (1)

Mermaid Viewer v1.0

A Mermaid diagram viewer with history tracking, font size adjustment, and image export support.

Start Diagramming Today

No account needed. No internet required.

Download for Mac

macOS 13+ · Apple Silicon native · Under 30MB