MacMD Viewer vs. MarsDawn.

Both are Mac apps for reading Markdown as a finished page. MacMD Viewer opens a .md file and shows it; it is read-only by design and never saves changes to your file. MarsDawn puts an editor next to the same kind of rendered preview, so you write and review in one window. This page sets the two side by side, row by row, with a source for every fact about MacMD Viewer, and says when MacMD Viewer is the better choice.

Checked against MacMD Viewer's own site and repository on 15 October 2026 (version 1.7.0, released 10 October 2026). If something here is out of date, tell us at the address on the support page.

What it is and what it does

	MacMD Viewer	MarsDawn
What it is	A viewer: "read-only and never saves changes to your source file" [S1, S9]	An editor with a live preview: Markdown on the left, the rendered page on the right, in three layouts (source, split, preview)
Editing	No [S1, S7, S9]	Yes. The rendered page itself isn't editable; you edit the source beside it
Live preview	Renders the file; reloads when the file is saved by another editor [S9]	Updates as you type. When another app changes the file, MarsDawn reloads it and keeps your place, as long as you have no unsaved edits of your own.
Mermaid	Yes: flowcharts, sequence, state and Gantt diagrams, pie charts and more, offline [S1, S3, S7]	Yes
Math	No: its README says it "does not render math (LaTeX/KaTeX)" [S7]	Yes, KaTeX
Code highlighting	Yes [S1, S9]	Yes
Themes	12 document themes [S1, S7]	4 built in (Dawn, Classic, Modern, Vivid), each with a light and a dark palette, plus more in the theme gallery
Tabs	Yes, optional and off by default (since 1.6.0) [S5, S8]	Yes
PDF export	Yes, one continuous page, in the current theme, no watermark [S3, S9]	Yes, paginated pages in the theme's light palette; page breaks avoid splitting short code blocks
Print	Yes, through the macOS print dialog [S3, S9]	Yes
Quick Look in Finder	Yes, included; you enable it in System Settings; uses your theme [S4]	Yes, works with or without the trial; uses your theme
Mermaid and math in Quick Look	Mermaid: yes [S4]. Math: no, it doesn't render math [S7]	Yes, both are drawn
Command line	No standalone command-line tool is described. It has a `markdownviewer://` URL scheme and a Claude Code plugin and hooks that open files in the viewer [S6]	The free `marsdawn` tool: `marsdawn export` renders a PDF without the app, `marsdawn open` opens a file at a line
Interface languages	Not stated in its own materials [S1, S3, S7]	English, Traditional Chinese, Simplified Chinese, Japanese, German, French, Spanish and Korean
Requires	macOS 14 (Sonoma) or later; Apple Silicon and Intel [S1, S7]	macOS 26 (Tahoe) or later
Other platforms	Mac only [S1]	Mac, plus iPhone and iPad for reading only

Price and how you buy it

	MacMD Viewer	MarsDawn
Where you buy it	Its own site, Homebrew or Setapp; no Mac App Store listing [S2, S7]	The Mac App Store only
Price	USD 19.99 once, for one active Mac (movable to another Mac); Family Pack USD 39.99 for 3; 10 keys USD 129 [S2]	Free download, then USD 4.99 once
Trying it first	No trial or free tier; 14-day full refund on direct purchase [S2]	14-day free trial with everything on
Refunds	Through its own support, within 14 days [S2]	Through Apple
Updates	Updates within the current major version are free [S2]; the direct download updates itself with Sparkle [S7]	Through the Mac App Store
Account needed	No [S2]	No
Subscription	No [S1, S2]	No

What changes if you stop paying or trying

	MacMD Viewer	MarsDawn
After the trial or purchase window	No trial; keeps working once bought	If you don't unlock after 14 days, documents open with their content covered; your files are untouched, Quick Look and the free `marsdawn` export keep working

Sources

S1 · https://macmdviewer.com/
S2 · https://macmdviewer.com/pricing
S3 · https://macmdviewer.com/features
S4 · https://macmdviewer.com/quicklook
S5 · https://macmdviewer.com/changelog
S6 · https://macmdviewer.com/docs/integrations
S7 · https://github.com/macmdviewer/MacMDViewer
S8 · https://macmdviewer.com/press
S9 · https://macmdviewer.com/product-facts.md
S10 · https://github.com/macmdviewer/MacMDViewer/releases

Which one to pick

Pick MacMD Viewer if you only read Markdown and you want that to be guaranteed: it never saves changes to your file [S1]. It also fits better if your Mac runs macOS 14 or 15, since MarsDawn needs macOS 26 [S1, S7]; if you would rather buy from a developer's own site, Homebrew or Setapp than the Mac App Store [S2, S7]; if you want files an agent edits to open in the viewer automatically, which it does through hooks for Claude Code, Cursor and Windsurf [S6]; or if you want a single continuous-page PDF rather than paginated pages [S9]. It has no trial, but it has a 14-day refund [S2].

Pick MarsDawn if the Markdown comes back for another pass. An agent's plan, README or spec usually needs a fix, a reworded line or a new section, and in MarsDawn you do that in the window where you are already reading. It also covers math (KaTeX), which MacMD Viewer says it doesn't render [S7]; it ships in eight interface languages; it has a free marsdawn command line that exports a PDF without the app; and its price is USD 4.99 after a 14-day trial in which everything works.

Either works if you read Markdown on a recent Mac, want Mermaid diagrams drawn properly and want Quick Look in Finder. Both do those.

And you can use both. They aren't exclusive: nothing stops you from keeping a read-only viewer for what you only read and an editor for what you write.

Questions

Does MacMD Viewer edit files?

No. It is read-only and, in its own words, never saves changes to your source file [S1, S9]. It can open the file in your text editor (File menu, ⇧⌘E, since 1.7.0), which hands the file to another app [S5].

Is MacMD Viewer on the Mac App Store?

Its own pages list its site, Homebrew and Setapp, and don't mention the Mac App Store [S2, S7]. MarsDawn is on the Mac App Store only.

Can MarsDawn open the same files?

Yes. It opens .md files, and also plain text files and PDFs: text opens ready to edit as UTF-8, and PDFs open in a viewer.

What if I'm on macOS 14 or 15?

MacMD Viewer runs on macOS 14 or later [S1]. MarsDawn needs macOS 26 or later, and the free marsdawn command-line tool can still export a PDF.

Why is one USD 19.99 and the other USD 4.99?

They differ in what you get and how you pay. MacMD Viewer is a one-time purchase with a 14-day refund and no trial [S2]. MarsDawn is a free download with a 14-day trial, then a one-time unlock. Neither is a subscription.

Try it today, free

MarsDawn is on the Mac App Store. The free marsdawn command-line tool also renders any Markdown file to a PDF, with Mermaid diagrams and highlighted code, and needs nothing else installed:

brew tap redtear1115/tap && brew install marsdawn
marsdawn export notes.md
open notes.pdf

The full walk-through: Markdown to PDF.
What MarsDawn doesn't do: the list.
Every option of the command-line tool: Command Line.
Compared with reading Markdown in VS Code, a browser or Claude Desktop instead: how they compare.
All of MarsDawn's features on one page: Features.