Question 1

How does Markdown to HTML conversion work?

Accepted Answer

A Markdown parser reads the source text and produces an abstract syntax tree (AST), which is then serialized to HTML. # heading becomes

, ** bold** becomes , [text](url) becomes , fenced code blocks become
, etc. The exact output depends on which Markdown flavor the parser supports (CommonMark, GFM, etc.). Most parsers are written in the target language — marked.js and markdown-it for JavaScript, Python-Markdown, commonmark.rb for Ruby.

Question 2

Can I use the HTML output from Markdown in emails?

Accepted Answer

Yes, but email HTML has significant constraints. Email clients do not support external CSS,

Question 3

What Markdown extensions does the converter support?

Accepted Answer

This converter supports GitHub Flavored Markdown (GFM) extensions on top of CommonMark: tables (| col |), task lists (- [x]), fenced code blocks with syntax hints (```js), strikethrough (~~text~~), and autolinks. It does not support non-standard extensions like math (LaTeX/KaTeX), footnotes, or custom directives — those require specific Markdown parsers.

Question 4

Is the HTML output safe to render directly in a browser?

Accepted Answer

Raw Markdown-to-HTML conversion can include any HTML that was present in the Markdown source. If the input is user-supplied, you must sanitize the output before inserting it into the DOM to prevent XSS attacks. Use a library like DOMPurify (browser) or sanitize-html (Node.js) after conversion. For trusted content (your own documentation), rendering the raw output is safe. Never use innerHTML with unsanitized user Markdown.

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