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Markdown Converter

Convert GitHub Flavored Markdown and sanitized HTML locally, with a safe rendered preview.

Runs locally — input is never uploaded
Markdown or HTML · max 10 MiB
Preview & outputReady when you are

Converted content will be previewed here.

WHAT IT DOES

Move between Markdown and HTML without trusting either one.

Convert GitHub Flavored Markdown to a sanitized standalone HTML file, or turn sanitized HTML into readable Markdown, entirely in the browser. The rendered panel shows what the converted document means while the output remains available as copyable text and a local .html or .md download.

Why use it?

Use it to move document content between Markdown and HTML while reviewing the structure that survives the conversion.

How to use this tool

  1. Paste the source and explicitly choose Markdown to HTML or HTML to Markdown.
  2. Convert and compare the rendered preview with the output text. A heading such as # Release notes should remain a heading rather than literal punctuation.
  3. Copy or download the result, then review tables, links, and code blocks in the destination. Sanitization and format differences mean this is not a byte-preserving round trip.

Details and limitations

  • Markdown input uses GitHub Flavored Markdown for tables, task lists, fenced code, strikethrough, links, images, lists, headings, emphasis, and blockquotes.
  • Generated and supplied HTML is sanitized before it is previewed or passed to the reverse converter; scripts, handlers, dangerous URLs, embedded frames, forms, and inline styles do not survive.
  • HTML-to-Markdown preserves common headings, paragraphs, links, images, lists, tables, code blocks, blockquotes, and emphasis where GitHub Flavored Markdown has a direct representation.
  • HTML downloads are standalone documents with UTF-8 and viewport metadata and no scripts, runtime CDN, stylesheet dependency, or remote conversion step.

COMMON QUESTIONS

Markdown Converter questions

Which Markdown flavor does this use?
GitHub Flavored Markdown, including tables, task lists, fenced code blocks, and strikethrough. Other Markdown dialect extensions are not claimed.
Can pasted HTML execute scripts?
No. HTML is treated as untrusted text and sanitized before preview or reverse conversion. Scriptable elements, event attributes, unsafe URLs, frames, forms, and inline styles are removed.
Is the downloaded HTML self-contained?
Yes. It is a small standalone UTF-8 document with no CDN or runtime dependency. Remote images or links that remain in safe content still point to their stated destinations when the downloaded file is opened.