A free, native Markdown viewer and reader for macOS. Open any .md file from Finder, iCloud, Dropbox, or a Git repo — render GitHub-flavored Markdown instantly with auto table of contents, syntax highlighting, and live WYSIWYG editing. 100% offline, no setup.
Free • Offline • macOS 10.13+
MarkViewer is a lightweight Markdown reader and editor for Mac. Double-click any .md file in Finder and it opens — no IDE, no browser, no uploads. The rendered view is the edit view, so you can preview Markdown and make quick fixes in the same window.
If you've been searching for a clean Markdown viewer for Mac — this is it.
MarkViewer applies formatting instantly as you type markdown syntax. No separate preview pane needed. See exactly how your markdown will render, right as you write.
Type markdown syntax and see it rendered instantly. Headings, bold, italic, links — all formatted as you write.
Automatically generated TOC from your headings. Navigate long documents with ease.
Code blocks are highlighted with proper syntax coloring. JavaScript, Python, Go, and more.
Full GitHub Flavored Markdown support. Tables, checklists, strikethrough — all rendered perfectly.
Launches in under a second. No workspace loading. Just open your .md file and start writing.
Everything runs locally. No cloud, no uploads, no tracking. Your documents stay on your Mac.
MarkViewer isn't trying to replace a full writing environment or your main code editor. It's for when you need to:
Three steps from a fresh download to a fully rendered .md file.
MarkViewerMarkViewer.app into Applications and launch.
.md file.
Double-click a markdown file in Finder, drag it onto the MarkViewer dock icon, or use ⌘O from inside the app. The file renders immediately — headings, tables, task lists, and fenced code blocks formatted the way GitHub renders them.
.md.
In Finder, right-click any markdown file → Get Info → Open With → choose MarkViewer → click Change All…. From then on, every .md file you open from Finder, Spotlight, or another app lands in MarkViewer.
MarkViewer requires macOS 10.13 or later and runs as a universal binary on both Apple Silicon and Intel Macs.
MarkViewer supports the GitHub Flavored Markdown (GFM) feature set, so what you see while editing matches what GitHub renders for the same file. There is no separate preview pane — the rendered view is the edit view.
Pipe-delimited tables, alignment markers (:---:), and - [ ] task lists render exactly as they do on GitHub, including nested checklists and mixed-indent lists.
Triple-backtick code blocks are syntax-highlighted for over 100 languages — JavaScript, TypeScript, Python, Go, Rust, Shell, SQL, YAML, and more. Click to copy any block.
Flowcharts, sequence diagrams, ER diagrams, and class diagrams render inline from ```mermaid blocks. No external service round-trip and no internet required.
Bare URLs become clickable. Reference-style links ([label][ref]), inline images, and footnotes resolve correctly. External links open in your default browser.
The full GFM emphasis set: bold, italics, strikethrough, and inline code — all formatted live as you type the syntax.
Each heading produces a stable anchor used by the auto-generated table of contents in the left rail. Click any TOC entry to jump; the active heading updates as you scroll.
MarkViewer reads from any location your Mac can reach. Files stay in their original folder — MarkViewer does not copy them into a separate workspace, so changes you save sync back through whichever cloud provider hosts the file.
~/Library/Mobile Documents/… or via Finder. Saves write back to iCloud and propagate to your other devices.Files are loaded locally and never uploaded to any MarkViewer server. The app itself runs 100% offline — opening a Dropbox-hosted file does not send its contents anywhere except back to Dropbox when you save.
MarkViewer is built around a small, memorable shortcut set so you rarely need to reach for the mouse. All shortcuts can be remapped from ⌘, Settings.
MarkViewer is one of several ways to read and render .md files on macOS. Here's where it fits alongside the common alternatives.
Where MarkViewer is specialized: lightweight real-time preview for local .md files, with an inline AI review loop for handing annotated drafts off to Claude, ChatGPT, or Cursor in one keystroke.
If you regularly read AI-generated Markdown, MarkViewer adds an optional handoff layer on top of the viewer. Highlight a passage, leave an inline comment with ⌘⇧R, press ⌘⇧↵, and paste the generated prompt into Claude, ChatGPT, Cursor, Gemini, or Copilot. Optional, never required — the core app stays a clean Markdown viewer.
Press ⌘⇧R on any selection to leave a review comment. Annotations are stored as HTML comments inside the markdown, so they survive save/reload and don't affect rendering.
Press ⌘⇧↵ to open a floating panel with the rendered prompt. Edit freely, save as your default template, or reset.
Claude, ChatGPT, Cursor, GitHub Copilot, Google Gemini, Codex CLI, local LLMs — if it accepts pasted text, it works. No API key, no internet requirement inside MarkViewer.
MarkViewer never hijacks your clipboard. The prompt is only copied when you click Copy — no surprises, no stolen focus.
The pitch: AI writes drafts, humans review them. Until now, reviewing a Claude-generated README meant copy-pasting chunks back and forth. The AI Review Loop keeps your annotations attached to the file and makes the handoff one keystroke.
Install MarkViewer, then double-click any .md file or drag it onto the app icon. You'll see the rendered Markdown — headings, lists, tables, code blocks, task lists — with no browser and no internet connection. You can also set MarkViewer as the default app for .md files in Finder's Get Info panel.
Yes. MarkViewer renders Markdown as you type — headings, bold, italics, lists, tables, and code blocks format instantly. There is no separate preview pane to toggle; the rendered view is the edit view.
Yes. MarkViewer reads any .md file you have access to on your Mac, including iCloud Drive, Dropbox, Google Drive, and external volumes. Files are loaded locally — nothing is uploaded.
Yes! When Claude or ChatGPT generates markdown content, you can save it as a .md file and edit it in MarkViewer. The WYSIWYG editor makes it easy to fix formatting or add your own notes.
MarkViewer is a native macOS app that works 100% offline. No internet required, no files uploaded to servers. It's also faster than browser tools and integrates with your Mac's file system.
MarkViewer supports GitHub Flavored Markdown (GFM) including tables, task lists, and code syntax highlighting. The rendering is very close to what you'll see on GitHub.
MarkViewer focuses on viewing and editing Markdown files, not exporting them. For PDF or HTML output, consider a dedicated conversion tool. MarkViewer's strength is being lightweight and fast for everyday Markdown preview and review.
Yes — MarkViewer's AI Review Loop lets you annotate any passage, then press ⌘⇧↵ to open an editable prompt panel. Copy the prompt into Claude, ChatGPT, Cursor, Gemini, or any AI assistant.
No. MarkViewer itself is 100% offline and never contacts any AI service. You paste the generated prompt into whichever AI tool you already use — the review loop is a handoff, not an integration.
Open and read .md files on macOS the simple way. Free for macOS 10.13 and later.
Download for Mac (Free)Universal Binary (Intel & Apple Silicon)