Mello
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Markdown ↔ HTML Converter

Convert between Markdown and HTML, with a live rendered preview for Markdown.

Runs in your browserNo account requiredNo uploadFree
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About Markdown ↔ HTML Converter

Markdown ↔ HTML Converter goes both directions: Markdown to ready-to-paste HTML, or HTML back to clean Markdown. Markdown is easier to write — readable on its own, no angle brackets to mind — while HTML is what browsers render and what most CMSs store. Being able to flip between the two is useful whenever you are moving content between a note-taking app, a static-site repo, a blog editor, and an email.

Worked example: the Markdown '# Hello\n\nSome **bold** text with a [link](https://example.com).' becomes the HTML '<h1>Hello</h1><p>Some <strong>bold</strong> text with a <a href="https://example.com">link</a>.</p>'. Going the other way, paste a chunk of HTML and you get readable Markdown back. In MD→HTML mode a live rendered preview shows what the HTML actually looks like; HTML→MD shows the Markdown output only.

The dialect is GitHub-flavored Markdown (GFM): in addition to the basics, you get pipe tables, fenced code blocks with language tags, task lists (- [ ] / - [x]), strikethrough, and autolinks. Inline HTML inside Markdown is passed through. Two limits worth knowing: HTML that uses CSS classes, inline styles, or unusual structures may not round-trip exactly back into Markdown, because Markdown is the smaller of the two formats; and the tool does not sanitize HTML, so if you intend to render converted output as live HTML elsewhere, run it through a sanitizer first.

Conversion runs locally in your browser using the marked and turndown libraries. Drafts, unpublished posts, and internal documentation never leave your machine.

Frequently asked questions

GitHub-flavored Markdown (GFM): tables, fenced code blocks, task lists, strikethrough, and autolinks, in addition to the CommonMark basics.

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