Readdown

The Markdown reader macOS never shipped.
Double-click to read, spacebar to preview — nothing more.

Download for Mac · Website

Features

• Read-only — No edits, no auto-formatting. Your files stay untouched.
• Quick Look — Spacebar on any .md in Finder. Rendered, not raw.
• Lightweight — Native Swift. Opens in under a second, stays out of your way.
• Syntax highlighting — 19 languages auto-detected, or specify the language on your code fence.
• Math rendering — Inline ($x^2$) and display ($$\int f\,dx$$) TeX equations via KaTeX, fully offline.
• Mermaid diagrams — Flowcharts, sequence diagrams, pie charts, and more.
• Dark mode — Follows your system appearance automatically.
• Default reader — One click to replace Xcode or TextEdit as your .md handler.

Quick Look Setup

On first launch, Readdown walks you through this — but here are the manual steps:

1. Open System Settings > General > Login Items & Extensions
2. Click i next to Quick Look
3. Toggle Readdown on

Download

Get the latest release from GitHub Releases.

Requires macOS 13 Ventura or later.

Build from source

1. Clone the repo
2. Open ReadDown.xcodeproj in Xcode
3. Build and run (requires macOS 13+)

Feedback

Found a bug or have a feature request? Open an issue.

License

Source-available. You may view, study, and contribute, but redistribution is not permitted. See LICENSE for details.

Support

If you find Readdown useful, you can buy me a coffee.

Sponsor a release

Each Readdown release can be sponsored, with a credit on the website, in the GitHub release notes, and here. To become a release sponsor, reach out at hello@readdown.app.