Most Markdown is already open in an editor
If you write code, the Markdown you read probably lives in a repository, and VS Code is already open on it. Its built-in preview is free, sits next to the source and needs no extra app. For many developers it is the default Markdown reader, and a fair comparison has to start there.
This page compares that preview with a dedicated reader. It is not an argument that you should stop using VS Code. It is about which tool fits which moment: editing a document, or reading through one.
Features compared
Scroll sideways to compare both apps →
| Need | VS Code Markdown preview | Aero Markdown |
|---|---|---|
| Open a preview | Open Preview (⇧⌘V) or preview to the side (⌘K V), with scroll sync. | The rendered page is the main view; source appears when you edit. |
| Diagrams and formulas | Built-in rendering of Mermaid code blocks and KaTeX math. | Mermaid and KaTeX bundled in the app. |
| Headings | Outline view in the Explorer; workspace-wide header search. | Heading outline beside the page. |
| Links between files | Path completions while writing; link validation (off by default) and Find All References. | Follow relative links in the reading window, with back and forward. |
| Folder context | The full workspace Explorer, alongside every other project file. | A file tree of the Markdown folder you opened. |
| Changed files | The preview updates with the editor. | Reloads the open file at the current heading; unsaved edits are kept. |
| Security | Preview security is Strict by default: no scripts, no http images. | Renders local files; no account, no network needed to render. |
| Finder | No Quick Look extension. | Includes a Finder Quick Look extension. |
| Export | The built-in Markdown docs don't describe PDF export; extensions add it. | Print, export to PDF or save a local HTML file. |
| Cost | Free, cross-platform editor. | Aero Markdown is $14.99 USD, one-time, for a lifetime Aero 1.x license for one Mac. Download and checkout are not available yet. |
Facts about VS Code come from its Markdown documentation. Check it against the version you use; the preview has gained features, such as Mermaid rendering, over time.
Where the VS Code preview is the better choice
When you are writing or editing Markdown, the side-by-side preview is hard to beat. Scroll sync keeps both panes aligned, path completions help you write correct links and image paths, and link validation can warn you about a link to a renamed heading or a deleted file. If a document is part of a code change, reviewing it in the same editor and the same diff keeps everything in one place.
It is also free, and you already have it. If you rarely read Markdown outside a coding session, a separate reader may add nothing for you.
Where a dedicated reader helps
The editor is built around the source. Reading a long plan, a specification or a report written by a coding agent is a different activity. You want the rendered page in front of you, the outline to find your place and the next linked document one click away, without tabs, terminals and every other file in the repository competing for attention.
Aero Markdown is built for that. The page is the main view, the folder sits in a tree, relative links open in the same window and back returns you to where you were. When an agent rewrites the file you have open, the page reloads at the same heading, so you keep reading instead of searching for your place. Optional local hooks let Claude Code, Cursor and Windsurf open the Markdown they write in the existing window.
It also works outside a repository. A folder of notes in Documents, a ZIP someone sent you or a README you downloaded can be opened directly, and the Finder Quick Look extension previews them before you open anything.
A practical way to split the work
Many people will use both. Write and review Markdown changes in VS Code, where the source and the diff live. Read finished documents, long plans and agent output in a reader, where the page comes first.
To see the difference with your own files, open the Project Reading Kit in VS Code and in a reader. Start at README.md, follow the link to the specification, open a decision record and come back. Notice how many tabs, panes and clicks each one needs. For reading what agents write, see read Markdown written by coding agents.
BEFORE YOU CHOOSE
Questions, answered.
Does VS Code's Markdown preview render Mermaid and math?
Yes. Its documentation describes built-in rendering of Mermaid diagrams in mermaid code blocks and of math equations with KaTeX.
Can VS Code export Markdown to PDF?
The built-in Markdown documentation doesn't describe a PDF export; extensions add one. Aero Markdown can print, export to PDF or save a local HTML file.
Why use a separate reader if I have VS Code?
Only if you read Markdown outside an editing session often enough: long plans, specifications, agent reports or folders outside a repository. For writing and reviewing changes, VS Code is the better place.
Sources & method.
HOW WE COMPARE
Written by the team building Aero Markdown. Official product documentation reviewed . These are documented workflow comparisons, not hands-on performance tests. Aero Markdown’s Mac app and checkout are not public yet.
We link the sources, acknowledge shared capabilities and leave unverified behavior open. Prices and releases can change; check the developer’s current terms.