Short answer: paste HTML above and the Markdown output appears as you type. Headings, lists, tables, code blocks and links are converted to GFM syntax; styling, scripts and embedded media are dropped because Markdown has nowhere to put them.
What converts cleanly
- Headings h1–h6, paragraphs and line breaks.
- Bold, italic, strikethrough and inline code.
- Ordered, unordered and nested lists, plus task lists.
- Tables with a header row, as pipe tables.
- Code blocks with their language hint, and block quotes.
- Links and images with their text and alt attributes.
What Markdown cannot hold
CSS, layout, colours, web fonts, iframes, video, audio, canvas, SVG and form controls have no Markdown equivalent. They are removed rather than converted into something that only looks similar, and the report under the result says which kinds were dropped.
Why convert HTML to Markdown here
Documentation, emails and CMS exports are often HTML when you need plain text for a README, a wiki or a commit. Doing it in the browser means the source document — which may be an invoice, a draft or an internal page — never leaves your device. The reverse direction is also available: Markdown to HTML.