MarsDawn: Markdown Editor
Live preview, diagrams & PDF
Only for Mac
Free · In‑App Purchases
Mac
A native Mac editor for Markdown. Write on the left and read the rendered page on the right, with Mermaid diagrams and four preview themes. Free to try for 14 days.
Read what your agent wrote.
MarsDawn is a Markdown editor built for the Mac. Write in a native text editor on the left. The rendered page on the right updates as you type.
What it doesn't do
• No account, no sync and no cloud. Your documents stay where you save them on your Mac.
• No iPhone or iPad app. MarsDawn is for the Mac.
• No plugins or extensions.
• Four built-in themes, each in light and dark. You can't install others.
Write and read side by side
• Source, split and preview layouts, one keystroke apart (⌘1, ⌘2, ⌘3).
• The two panes scroll together, so the paragraph you are editing stays in view.
• Markdown syntax highlighting in the editor, matched to your preview theme.
Diagrams and code
• Mermaid flowcharts, sequence diagrams and more, drawn right in the preview.
• Code blocks get syntax highlighting, and tables, task lists, block quotes and images render too.
Four preview themes
• Dawn has warm paper and rust accents. Classic sets text in a serif, like a printed page. Modern is plain and blue. Vivid is rounded, with pink and purple.
• Every theme comes in Light and Dark, with text contrast that meets WCAG AA.
Share it as a PDF
• Export as PDF or print, in your theme's light colors. Page breaks avoid leaving a heading at the bottom of a page or splitting code, tables and diagrams.
• Works from any layout, even while only the source is showing.
Images
• Drop or paste an image into a saved document. MarsDawn copies it into an assets folder beside the document and writes the link.
• Local images show in the preview once you grant access to their folder.
• Web images stay blocked until you choose to load them, so opening a document never tells a server you read it.
Works with Siri and Shortcuts
• Start a new document from a template, add a line to your notes inbox, or reopen a recent document.
Made for the Mac
• Press Space on a Markdown file in Finder for a Quick Look preview, diagrams included.
• Open plain text files and PDFs to read them: text read-only in the editor, PDFs in a viewer with page thumbnails, zoom and search.
• Native windows, tabs, autosave and version history.
Free to download, 14 days to try
• Downloading is free. The first time you open MarsDawn, you can start a 14-day free trial. Everything works during the trial.
• After 14 days, reading and editing documents in MarsDawn needs a one-time unlock.
• No subscription. The trial doesn't renew or charge you. Your files never change, and Quick Look in Finder still shows them.
• English, Traditional Chinese, Simplified Chinese and Japanese.
• No tracking.
A new dawn for Markdown.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, Nan-Kuang Lee, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Nan-Kuang Lee
- Size
- 8.5 MB
- Category
- Developer Tools
- Compatibility
Requires macOS 26.0 or later.
- Mac
Requires macOS 26.0 or later.
- Mac
- Languages
English and 7 more
- English, French, German, Japanese, Korean, Simplified Chinese, Spanish, Traditional Chinese
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Unlock MarsDawn $4.99
- 14-day Trial $0.00
- Copyright
- © 2026 Nan-Kuang Lee
