Markdown / HTML変換

This is a two-way converter between Markdown and HTML. Turn Markdown into clean HTML to paste into a CMS, email or template, or convert existing HTML back into tidy Markdown for documentation and notes. A live preview shows the rendered result as you type.

Markdown is a lightweight way to write formatted text using plain characters, # for a heading, * for emphasis, - for a list, so it stays readable as source and converts cleanly to HTML. It powers README files, many docs sites, chat apps and static blogs.

The converter uses GitHub-Flavored Markdown, so headings, bold and italics, links, images, ordered and unordered lists, tables, blockquotes and fenced code blocks all convert as you would expect from GitHub or most modern Markdown tools.

The preview renders inside a sandboxed frame that cannot execute scripts, so even HTML containing embedded scripts is displayed safely. That matters when you paste HTML from an unknown source just to see or convert it.

Common uses include drafting content in Markdown and exporting the HTML a platform needs, cleaning messy HTML from a page into readable Markdown, or simply checking how a snippet will render before publishing it.

Everything runs locally in your browser, which keeps it fast and private. The text you convert never leaves your device.