Beautiful rendering, instant preview, table of contents, syntax highlighting, KaTeX math, Mermaid diagrams — and a built-in split-view editor. All in a native macOS app.
Requires macOS 14 Sonoma or later · Apple Silicon only
The idea for MDViewer came from wanting a lightweight way to read .md files when working with Claude Code or Codex from the terminal.
Then we wanted to edit them too — so v1.1 adds a built-in split-view editor. Viewer on the right, editor on the left, live preview as you type.
Features
Designed for developers, writers, and anyone who works with Markdown files every day.
Opens and renders Markdown files instantly. Watches for file changes and live-reloads as you edit.
Auto-generated TOC sidebar from headings. Click to jump to any section with smooth scrolling.
Visual thumbnail strip lets you browse long documents at a glance and jump to any page.
27 languages highlighted with Shiki. Light and dark themes that follow macOS appearance.
Render inline and block LaTeX math beautifully with KaTeX — no extra setup required.
Flowcharts, sequence diagrams, Gantt charts, and more rendered directly in the document.
Local Markdown links open in the app. External links open in the browser. Images load from disk.
Print or export your document to PDF with a single click, preserving all styles and formatting.
Toggle a split-view editor with ⌘E. Edit on the left, live preview on the right. Save with ⌘S.
Distributed with Developer ID signing and Apple notarization for safe, Gatekeeper-friendly installation.
Get started
No Homebrew, no setup, no configuration needed.
Unzip the archive and drag MDViewer.app to your Applications folder.
Double-click any Markdown file or drop it onto the MDViewer icon in the Dock.
Open Source
MDViewer is built on these open-source libraries. Full license texts are included in the app bundle.
| Library | Purpose | License |
|---|---|---|
|
v12.0.2
|
Parses Markdown text and converts it to HTML for rendering. | MIT |
|
v1.x
|
Syntax highlighting for 27 programming languages using VS Code grammar. Supports dual light/dark themes via CSS variables. | MIT |
|
v0.16.11
|
Renders LaTeX math expressions — both inline $…$ and block $$…$$ — as high-quality HTML. |
MIT |
|
v10.x
|
Renders diagrams from text definitions — flowcharts, sequence diagrams, Gantt charts, and more. | MIT |