Is MarkdownLab free to use?

Yes. MarkdownLab is 100% free, open-source, and requires no account. Every feature — Mermaid diagrams, KaTeX math, PDF export, multi-file projects — is available without payment or sign-up.

Does MarkdownLab work offline?

Yes. After the first load, MarkdownLab runs entirely in your browser. Your documents are saved locally via IndexedDB and never leave your device. No server, no telemetry, no tracking.

What markdown flavors does MarkdownLab support?

MarkdownLab supports GitHub Flavored Markdown (GFM), including tables, task lists, strikethrough, autolinks, footnotes, heading anchors, and fenced code blocks with language-aware syntax highlighting.

Can I render Mermaid diagrams in MarkdownLab?

Yes. Fence any block with ```mermaid and MarkdownLab renders flowcharts, sequence diagrams, class diagrams, state diagrams, ER diagrams, Gantt charts, and more. Diagrams open in a zoomable lightbox and export as high-resolution PNG.

Does MarkdownLab support LaTeX math?

Yes. Inline math uses $...$ and block math uses $$...$$. MarkdownLab renders equations with KaTeX, which is faster and more accurate than MathJax for most use cases.

How do I export markdown to PDF?

Click Export → Download PDF. MarkdownLab uses your browser's native print engine, so output is crisp vector text (not a rasterized screenshot) with proper pagination, footnotes, and working hyperlinks.

Yes. MarkdownLab is a static site — there is no backend, no analytics, no tracking pixels, and no cookies. All documents are stored in IndexedDB on your device. You can inspect the source on GitHub.

MarkdownLab — Free Online Markdown Editor with Mermaid & LaTeX

Is MarkdownLab really free?

Yes — free and open source under the MIT license. Every feature is available without payment, sign-up, or email capture.

Does it work offline?

Yes. After the first page load, MarkdownLab runs entirely in your browser. Documents persist in IndexedDB and survive reloads and browser restarts.

Is my markdown private?

Completely. No backend, no analytics, no cookies. Documents never leave your device. You can verify the source on GitHub.

Which markdown flavor is supported?

GitHub Flavored Markdown (GFM) via the marked parser, plus heading-ID and footnote extensions.

Can I render Mermaid diagrams?

Yes — any fenced block tagged mermaid renders as an interactive diagram with pinch / wheel / keyboard zoom and PNG export.

Does it support LaTeX math?

Yes, via KaTeX. Use $…$ for inline math and $$…$$ for block math.

Can I open a README directly from GitHub?

Yes. Use Import → Load from GitHub URL and paste a blob URL (github.com/{owner}/{repo}/blob/{ref}/{path}.md), a raw URL, or a bare repo URL — the default branch and README are resolved automatically. You can also share a direct deep link by appending the GitHub URL after the domain (markdownlab.vercel.app/https://github.com/owner/repo/blob/main/README.md) or as a query (?url=…); the file loads on page open. Relative .md links lazy-fetch on click; images and media resolve to raw.githubusercontent.com. Public repos only.

How do I export to PDF?

Export → Download PDF uses the browser's native print engine for crisp vector output with real pagination and working hyperlinks.

What browsers are supported?

Any modern browser with ES Modules support: Chrome, Firefox, Safari, Edge, Brave, and Arc, on desktop and mobile.