Free tool
Markdown to HTML.
Paste Markdown or drop a .md file and get clean HTML — tables, code blocks, lists and Mermaid diagrams included. It runs entirely in your browser. Copy the markup, download a standalone page, or turn it into a link people can open and comment on.
README.md
1.0 KBStays in your browser — nothing uploads.
Publishes the converted document to Comma: one URL, private or open to anyone with the link, and readers can comment on the exact paragraph, table row or code block. Free, no card.
Questions
- How do I convert Markdown to HTML?
- Paste the Markdown into the editor on this page, or drop a .md file onto it. The HTML is generated as you type — copy it, download it as a standalone .html file, or turn it into a shareable link. Nothing installs and nothing uploads.
- Which Markdown syntax is supported?
- Headings, bold, italic, inline code, links, images, bullet and numbered lists, blockquotes, horizontal rules, fenced code blocks with a language hint, GitHub-flavored pipe tables, and ```mermaid diagrams. It is the same converter Comma uses to render Markdown reports.
- Does it render Mermaid diagrams?
- Yes. A ```mermaid fenced block draws as a diagram in the preview, the downloaded page and the shareable link — flowcharts, sequence, Gantt, class, state and ER diagrams. The HTML output includes the Mermaid script (loaded from cdn.jsdelivr.net) only when the document contains a diagram; without one, the output is plain script-free HTML.
- Is my Markdown uploaded anywhere?
- No. The conversion happens in your browser and the preview renders in a sandboxed iframe on this page. The content only leaves your machine if you click “Get a shareable link” and create a report.
- What is the difference between the HTML fragment and the full page?
- The fragment is just the converted body — paste it into a template, an email, or a CMS. The full page wraps that fragment in a complete HTML document with readable default styles, so it opens correctly on its own in any browser.
- Are links and images sanitized?
- Yes. Only http, https, mailto and tel URLs survive conversion; javascript:, data: and file: URLs are replaced with #, and raw HTML in the source is escaped rather than executed. The only script ever added is the Mermaid loader, and only when a ```mermaid block is present. That is the same rule the Comma editor applies.
- How do I turn Markdown into a shareable web page?
- Click “Get a shareable link”. You land in the Comma editor with the converted document already loaded; save it and you get a URL you can keep private, make invite-only, or open to anyone with the link — and readers can leave comments anchored to the exact paragraph, row, or code block. Comma is free.
- Can an AI agent do this without the browser?
- Yes. Agents post Markdown or HTML straight to Comma over the REST API or the MCP server with a comma_sk_… token, which is how Claude Code, Cursor and VS Code publish a report at the end of a run.
Working the other way round? HTML to Markdown · Mermaid viewer · HTML viewer · HTML to PDF · Image to Base64 · JSON to HTML table · CSV to HTML table · Markdown table generator · all free tools · share an HTML report · report types