Markdown is a plain text format for headings, lists, links, tables and code. Most sites, README files and note apps accept it, but a page or an email template often needs the HTML it stands for.
Paste or upload Markdown and the HTML appears as you type. It follows CommonMark and adds the GitHub Flavored Markdown extras: tables, task lists, strikethrough, autolinks and fenced code blocks. Switch to Preview to see the result, copy the HTML, or download it as a .html file. The preview and the output are sanitized so that scripts in pasted Markdown can never run. Everything happens in your browser.
Everything in CommonMark plus the GitHub Flavored Markdown extras: tables, task lists, strikethrough, autolinks and fenced code blocks with a language tag. Raw HTML inside the Markdown is passed through.
Yes. The preview is cleaned with DOMPurify before it is shown, so scripts, inline event handlers and javascript: links are removed and cannot run on this page. Sanitizing is also on by default for the HTML you copy or download, and you can turn it off if you trust the source.
Turn on Full page. The output then includes the doctype, a head with a title taken from your first heading, and a small stylesheet, so you can save it and open it directly in a browser.
By default a single line break inside a paragraph is ignored, as in standard Markdown. Turn on Line breaks to turn each one into a br tag, which is how GitHub comments behave.
No. Fenced code blocks become pre and code elements with a class such as language-js, so any highlighter you use on your own site can pick them up.
No. The conversion runs in your browser and nothing leaves your device.