Markdown Preview on Mac

Quick Look .md files in Finder, preview in a native app, or render online

macOS doesn't render Markdown preview out of the box — pressing Space on a .md file in Finder shows raw syntax instead of formatted text. Here's how to get proper Markdown preview on Mac, from the fastest one-key method to a full-featured viewer.

1. Quick Look Preview in Finder (Fastest)

MDViewer includes a built-in QuickLook extension that gives you instant Markdown preview right in Finder. Once installed, it works automatically:

  1. Select any .md, .json, or .mermaid file in Finder
  2. Press Space
  3. See a fully rendered preview — headings, code blocks with syntax highlighting, tables, and Mermaid diagrams

No plugins, no configuration. The extension installs with MDViewer and registers itself automatically. Works in Finder's column view, icon view, and full-screen Quick Look.

This is the fastest way to preview Markdown on macOS — one keypress, zero app launches. No other Markdown viewer offers a native QuickLook extension with this level of rendering.

2. Full Preview in MDViewer (Most Powerful)

For longer documents or when you need navigation, editing, or history, open the file in MDViewer directly:

  • Smart table of contents — tracks your scroll position, highlights the active section, click any heading to jump
  • Inline editing — double-click any word to edit, ⌘S to save, Esc to go back to preview
  • Git history — browse previous versions and see color-coded diffs for any commit
  • Tabs — open multiple .md files in one window
  • Mermaid diagrams — rendered as interactive SVGs with zoom and pan
  • Syntax highlighting — 180+ languages in fenced code blocks

Set MDViewer as your default app for .md files and every double-click in Finder opens a full Markdown preview with all of the above.

3. Online Markdown Preview (No Install)

Need a quick Markdown preview without installing anything? The MDViewer online viewer works in any browser:

  1. Open getmd.ma/viewer
  2. Drag and drop your .md file
  3. See it rendered with full GitHub Flavored Markdown support, syntax highlighting, and Mermaid diagrams

Your file stays on your device — it's processed locally by JavaScript, never uploaded to a server. Works on Mac, Windows, Linux, and mobile.

Other Ways to Preview Markdown on Mac

These alternatives work but come with tradeoffs:

  • VS Code Markdown Preview — press ⌘⇧V to open a preview pane. Full-featured, but VS Code is a 300 MB+ code editor — heavy for just previewing a README
  • Xcode — renders basic Markdown automatically when you open a .md file. Limited formatting, slow to launch
  • Marked 2 ($13.99) — dedicated preview companion for external editors. Good if you write in Sublime or BBEdit, but doesn't have its own editor or Quick Look
  • GitHub — renders Markdown in the web UI. Only works for files already in a repository, not local files
  • Third-party Quick Look plugins — exist but often break after macOS updates, require manual installation, and don't support Mermaid or syntax highlighting

Why MDViewer for Markdown Preview

  • Quick Look built in — the only Mac viewer with a native QuickLook extension for .md, .json, and .mermaid files
  • Native macOS app — built with SwiftUI, launches instantly, uses minimal memory
  • Free — no trial period, no feature limits, no ads
  • Three preview levels — Space in Finder for a glance, full app for deep reading, online viewer for cross-platform
Download MDViewer for Free

Requires macOS 13.0 or later. Intel and Apple Silicon.

FAQ

How do I enable Markdown Quick Look on Mac?

Install MDViewer. The QuickLook extension is bundled inside the app and registers automatically — no separate install, no System Preferences toggle. Just press Space on any .md file in Finder.

Does the Quick Look preview support code highlighting?

Yes. Fenced code blocks render with syntax highlighting for 180+ languages, including Python, JavaScript, Swift, and SQL. Mermaid diagrams are also rendered.

Can I preview Markdown without installing an app?

Yes. Use the free online Markdown viewer — drag and drop a file in your browser. It works on any operating system and doesn't upload your file.

What file types does the Quick Look extension support?

MDViewer's QuickLook extension renders .md, .markdown, .json, .mmd, and .mermaid files.