showmd

showmd is a native macOS Quick Look extension that renders Markdown files instead of showing raw text. When a user presses Space on a .md file, the extension displays the document with full GitHub‑flavored Markdown support, including syntax highlighting, emojis, footnotes, inline images, and GitHub‑style alerts. It also parses YAML front‑matter into a collapsible metadata table that is collapsed by default but can be expanded with a single click.

The tool is aimed at developers and content creators who work with Markdown on macOS and need a quick, readable preview without opening a separate editor or browser. It supports LaTeX math, Mermaid diagrams, and all common Markdown flavors, allowing diagrams and equations to be visualized directly in the preview pane. All rendering happens locally, keeping files private by default.

showmd distinguishes itself by integrating tightly with macOS Quick Look, providing instant rendering, a source‑view toggle, and specific handling of YAML front‑matter and AI‑generated XML tags. It is open‑source, free, and does not require any online account or cloud service.