Markdown to HTML Converter

It covers a core set of Markdown and nothing more: # headings (levels 1 to 6, with a space after the hashes), bullet lists starting with -, * or +, **bold**, *italic*, inline `code`, [text](url) links and fenced code blocks. The sample converts to:

The result is an HTML fragment, ready to paste into a page or a CMS field. There is no html, head or body wrapper and no stylesheet.

This converter works line by line. Two lines next to each other are not joined into one paragraph, as most Markdown renderers would do:

If you write with hard line breaks, for example text copied from an email or a terminal, put each paragraph on a single line before converting. Trailing double spaces are kept in the text but don't add a line break.

Anything outside the list above is left as text in a paragraph:

• Numbered lists, blockquotes, tables, strikethrough, underscore emphasis and horizontal rules are not converted.
• Indented sub-items are flattened into the parent list.
• An image becomes a link to the image file with a stray exclamation mark in front of it.
• Emphasis inside bold breaks the markup: **bold *inner* text** gives <p>*<em>bold </em>inner<em> text</em>*</p>.

Asterisks are also read inside inline code, so `a**b**c` gets a bold tag inside the code element.

Any HTML you type is escaped, so <div> shows up as visible text rather than becoming an element. Code blocks are escaped too, and the language name after the opening fence is dropped:

Link URLs are copied as they are, and the first closing bracket ends them. A URL that contains brackets itself, as some wiki addresses do, gets cut short. Replace those brackets with %28 and %29 first.

The converter doesn't check link targets, so a link to a javascript: address stays clickable in the output. Only convert Markdown you wrote or trust before publishing the HTML.