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Markdown to HTML Converter

Convert Markdown to clean, semantic HTML with live preview — supports GFM tables, task lists, syntax highlighting, and custom sanitization.

Last updated: March 25, 2026

Client-Side Processing
Input Data Stays on Device
Instant Local Execution

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What is Markdown to HTML Converter?

Markdown is a lightweight markup language created by John Gruber in 2004 that lets you format text using simple, readable plain-text syntax. `# Heading`, `**bold**`, `[link](url)`, and ```code``` are immediately readable even without rendering — making it ideal for README files, documentation, blog posts, and any context where the source text should be readable without a browser. Under the hood, Markdown is always transformed to HTML before it's displayed in a browser.

There are two major Markdown flavors: **CommonMark** (the stricter, interoperable specification) and **GitHub Flavored Markdown (GFM)**, which adds tables, task checkboxes, strikethrough, and autolinks. This tool supports GFM, the de-facto standard used by GitHub, GitLab, Notion, Obsidian, and most developer documentation systems. The generated HTML uses clean, semantic elements (`<h1>–<h6>`, `<strong>`, `<code>`, `<table>`) with no inline styles, ready for styling with your own CSS.

How to Use Markdown to HTML Converter

1

Type or paste Markdown in the left editor panel (supports # headings, **bold**, *italic*, links, images, `code`, tables, task lists)

2

The HTML output and rendered preview update live as you type — no button press required

3

Switch between "Raw HTML" and "Preview" tabs in the right panel to see the generated code and final render

4

Click "Copy HTML" to copy the clean HTML, or "Download HTML" to save a complete HTML file with a `<style>` block

5

Use the Options to toggle: sanitize raw HTML in input, add heading IDs for anchor links, or wrap in a full HTML document template

Common Use Cases

  • Converting a GitHub README.md to HTML for embedding in a documentation website or email newsletter
  • Converting Markdown blog posts to HTML for pasting into a CMS like WordPress, Ghost, or Webflow
  • Generating static HTML from Markdown documentation for a project site or help center
  • Previewing how Markdown will render on GitHub before pushing to the repository
  • Converting Markdown meeting notes or project specs to an emailable HTML document
  • Transforming Markdown content from a headless CMS into HTML for rendering in a React/Next.js app
  • Producing clean semantic HTML from AI-generated Markdown responses for use in web UIs
  • Converting Markdown API documentation (like Swagger descriptions) to HTML for developer portals

Example Input and Output

Converting a GFM document section with a table and task list to HTML:

Markdown input (GFM)
## Release Checklist

| Task | Owner | Status |
|------|-------|--------|
| Code review | @alice | ✅ |
| QA testing | @bob | 🔄 |

- [x] Write release notes
- [ ] Update changelog
- [ ] Tag release
Generated HTML output
<h2 id="release-checklist">Release Checklist</h2>

<table>
  <thead>
    <tr><th>Task</th><th>Owner</th><th>Status</th></tr>
  </thead>
  <tbody>
    <tr><td>Code review</td><td>@alice</td><td>✅</td></tr>
    <tr><td>QA testing</td><td>@bob</td><td>🔄</td></tr>
  </tbody>
</table>

<ul class="task-list">
  <li class="task-list-item">
    <input type="checkbox" checked disabled> Write release notes
  </li>
  <li class="task-list-item">
    <input type="checkbox" disabled> Update changelog
  </li>
  <li class="task-list-item">
    <input type="checkbox" disabled> Tag release
  </li>
</ul>

Client-Side Processing

All Markdown parsing and HTML generation runs in your browser using the marked.js or similar library. Your document content is never transmitted to our servers.

Adding CSS to the Generated HTML

Raw HTML from Markdown has no styling. For a clean document look, add a typography stylesheet: GitHub's Primer CSS for GitHub-style Markdown rendering (@primer/css), Pico CSS for minimal elegant typography, or Pandoc's default CSS. For React/Next.js, the @tailwindcss/typography plugin (prose class) perfectly styles raw HTML from a Markdown converter.

Server-Side Markdown Parsing

For production apps, parse Markdown server-side (not client-side) for better performance and XSS safety control. Recommended: marked (Node.js, fast), remark (highly extensible, unified ecosystem), showdown (browser + Node), or pandoc (CLI, supports 50+ formats). Next.js + MDX (Markdown + JSX) is the modern standard for documentation sites, allowing React components inside Markdown files.

Frequently Asked Questions

What is the difference between CommonMark and GitHub Flavored Markdown?
CommonMark (spec.commonmark.org) is the strict, standardized Markdown specification resolving the many ambiguities in Gruber's original 2004 definition. GitHub Flavored Markdown (GFM) is a superset of CommonMark that adds: tables (| col | col |), task list items (- [x] done), strikethrough (~~text~~), autolinks (bare URLs become clickable), and disallowed raw HTML tags (XSS-risky tags are stripped). This tool implements GFM, which is the most widely used flavor for developer content.
Is it safe to use the generated HTML directly in my website?
If the Markdown source is from trusted authors (yourself, your team), yes. If the Markdown contains user-provided input or untrusted content, you MUST sanitize the HTML output to prevent XSS attacks. Markdown allows raw HTML blocks — a malicious author could embed <script> tags or JavaScript event handlers. Enable the "Sanitize HTML" option in this tool to strip dangerous tags (script, iframe, on* attributes) using the DOMPurify library before using output in production.
How do I add syntax highlighting to code blocks?
In Markdown, fenced code blocks specify a language: ```javascript. The raw HTML conversion wraps this as <code class="language-javascript">. To add actual syntax highlighting, apply a client-side library like highlight.js (hljs.highlightAll()) or Prism.js to your page, or use a server-side highlighter like shiki or Chroma. This tool shows the code class attributes in the output for you to integrate with your preferred highlighting library.
Can I convert Markdown to a full standalone HTML document?
Yes. Enable the "Full Document" option to wrap the converted HTML in a complete HTML template: <!DOCTYPE html><html><head><meta charset="UTF-8"><style>/* minimal typography CSS */</style></head><body><!-- your content --></body></html>. This produces a self-contained .html file that renders correctly when opened directly in a browser — useful for sharing formatted documents without a web server.
Why does my Markdown table not convert correctly?
GFM tables require a header separator row with pipe and dash syntax: | column | column | on the first row, then | --- | --- | on the second row, then data rows. Common mistakes: (1) Missing the separator row — without it, the parser treats the pipes as literal text. (2) Misaligned pipes — each row must have the same number of pipe-separated cells. (3) No space around the pipe: |col| is not valid, | col | is. Enable "Show Source" to verify your table syntax.
Does this tool support Markdown with LaTeX/math equations?
Standard GFM does not include math equation support. LaTeX-style formulas ($E = mc^2$) are not part of the GFM specification. GitHub itself added math support (via MathJax) only in 2022 as a non-standard extension. This tool converts standard GFM only. For Markdown with math, use a library like markdown-it with the markdown-it-mathjax plugin, or KaTeX with a Markdown pre-processor that identifies math delimiters.

How This Tool Works

Markdown text is parsed using a GFM-compliant parser (marked.js or similar). The parser tokenizes the input into an AST (abstract syntax tree) with nodes for headings, paragraphs, code blocks, tables, and list items. Each node is rendered to its HTML equivalent. For task lists, list items starting with [x] or [ ] are converted to <input type="checkbox" checked/unchecked disabled> elements. The rendered HTML string is set as the innerHTML of the live preview container.

Technical Stack

marked.js / GFM parserDOMPurify XSS sanitizerCommonMark + GFM specificationClient-side only

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