Technical Markdown
Mermaid diagrams and KaTeX maths, rendered offline.
Technical documents are the ones a basic renderer fails. Imark is a free Markdown viewer for Mac with Mermaid diagrams, KaTeX maths, syntax-highlighted code, GitHub-flavored tables and task lists. The whole renderer is bundled with the app, so nothing is fetched and nothing is uploaded.
macOS 14+ · 6.7 MB
Published
One viewer for documents that are not just prose
Architecture notes, specifications, READMEs, research notes and agent plans mix writing with structure, and the structure is the part that usually breaks.
Mermaid diagrams
Flowcharts, sequence diagrams, state diagrams and the rest, rendered inline where the code block sits.
KaTeX maths
Inline and display equations, rendered locally, without sending the document to an online service.
Highlighted code
Fenced code blocks stay legible next to tables, task lists, links and images.
Works with the editor you already use
Write in Cursor, VS Code, Zed, Vim or anything else. Imark watches the file, re-renders after each save, and holds your scroll position so the document can live beside the editor instead of replacing it.
The same rendering in the app and in Finder
A diagram looks the same in the Quick Look preview as in the window. Glance at a file from Finder with the space bar, then open it properly when you need the outline, tabs, search, comments or PDF export.
Private by design
Documents render on the machine, remote requests from document content are blocked, and there is no account. That matters for private specifications and for repositories you are not allowed to paste into a browser.
Questions
What people want to know.
Does Mermaid work offline in Imark?
Yes. Mermaid is bundled with the app, so diagrams render with no connection at all.
Which maths syntax does Imark use?
KaTeX, for both inline and display equations written in the document.
Is there a free Markdown viewer for Mac with Mermaid?
Yes. Imark is free and open source, and renders Mermaid in both the main window and the Finder Quick Look preview.
Can Imark export technical Markdown to PDF?
Yes. Print a rendered document to PDF, with diagrams, maths and, if you want them, the visible comments.
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