Markdown Reader: A Quiet Three-Pane Workspace for macOS

Three panes make long Markdown files easier to scan

Markdown Reader puts a recursive folder tree, a rendered document and a heading outline side by side. Select a file from the tree, read the formatted page in the center, and use the outline to jump through a long document without losing its structure.

The layout is deliberately reader-first rather than an all-in-one writing suite. It aims to make opening a local .md file quick and quiet, while keeping folders and headings visible when you need to move around.

Rich rendering, with one network caveat

The app uses cmark-gfm and macOS’s native WebPage rendering for GitHub Flavored Markdown, including common document structures such as tables and task lists. Prism highlights code, while KaTeX handles LaTeX formulas.

Mermaid diagrams render locally, and optional runtimes such as Mermaid and KaTeX are loaded only when a document needs them. That keeps ordinary Markdown pages from loading every component up front.

PlantUML is supported too, but the project explicitly says it needs a network connection. So the app is convenient for local documents, but it would be inaccurate to describe every rendering path as fully offline.

A source editor, not just a read-only preview

Switch to the raw-source mode to edit Markdown directly and save with Cmd+S. The project says unsaved content is preserved when you switch files, so you can move through a folder without abandoning an in-progress edit.

The folder tree can also create, rename and delete files. Those actions affect the local files you opened; treat the app as a lightweight file workspace, not a read-only viewer.

There is no sign-up or login step in the documented workflow, but Markdown Reader is not a real-time collaborative editor. Its focus is opening, reading and editing files on your Mac, rather than syncing a team workspace.

Finder Quick Look and keyboard-first navigation

For a fast glance, select a Markdown file in Finder and press Space to use the app’s Quick Look preview without opening the main window. Quick Look can also copy the whole document, with a setting to choose rich text or raw Markdown.

Inside the app, Cmd+P opens the command palette, the outline jumps to headings, and familiar shortcuts cover find, find next and find previous. The app also remembers the last browsing position when you reopen it.

When a document needs to leave the app, Cmd+Option+E exports it to PDF. That makes the reader useful for reviewing and sharing a stable copy, even though it is not a publishing or collaboration service.

Themes and language choices for everyday reading

The project lists 33 themes—20 dark and 13 light—with custom color and contrast controls. You can tune a long reading session without changing the source document.

The app interface follows the system language and lists Simplified Chinese, Traditional Chinese and English. The repository also has localized README files; those documentation languages should not be mistaken for additional in-app interface locales.

Install v2.4.7 from the official Release

Download the official v2.4.7 DMG or ZIP, then move MarkdownReader into Applications. The project also maintains an official Homebrew tap and cask.

brew tap davidhoo/markdownreader
brew install --cask markdownreader

The release requires macOS 26 (Tahoe) or later and targets Apple Silicon. It is developer-signed but not notarized, so macOS may block the first launch. The project’s current guidance is to Control-click the app and choose Open, or use System Settings → Privacy & Security → Open Anyway; it does not recommend a Terminal command to bypass Gatekeeper.

MIT license and project links

Markdown Reader is open source under the MIT License. Check the repository and README, v2.4.7 Release, Homebrew cask and official website for current details.

open https://github.com/davidhoo/MarkdownReader/releases/latest/download/MarkdownReader.dmg