Markdown to HTML Preview

How to use this tool

1. Type or paste your Markdown. Replace the sample content in the editor with your own Markdown text. The preview updates instantly.
2. Check the live preview. The right pane (or "Preview" tab on mobile) shows the rendered result with headings, tables, code blocks, and all GFM elements.
3. Copy the HTML output. Copy the original Markdown or sanitized HTML, or download a .md file or standalone .html document for your next writing or publishing step.

What is Markdown?

Markdown is a lightweight plain-text formatting syntax created by John Gruber in 2004. It lets you write using an easy-to-read, easy-to-write format that converts cleanly to HTML. The idea is that Markdown should be readable as-is, without looking like it has been tagged up with HTML.

Most developers, technical writers, and documentation systems use Markdown today: GitHub, GitLab, Stack Overflow, Notion, Obsidian, Reddit, and hundreds of CMSes all support it.

GitHub Flavored Markdown (GFM)

This tool uses GitHub Flavored Markdown (GFM), a widely adopted superset of the original CommonMark specification. GFM adds:

• Tables: using pipe characters to define columns and rows.
• Task lists: checkboxes with - [ ] and - [x] syntax.
• Strikethrough: wrap text in ~~double tildes~~.
• Fenced code blocks: triple backticks can include a language hint such as ```js. The preview keeps code monochrome and emits that hint as a language-* class; it does not load a syntax highlighter.
• Auto-linking: bare URLs are turned into clickable links.

Markdown quick reference

Security: why HTML is sanitized

Markdown allows embedding raw HTML. While this is powerful, it also means a malicious source could include <script> tags, javascript: links, or inline event handlers like onerror=. This tool runs all output through DOMPurify, an industry-standard DOM sanitizer, before rendering or copying. Dangerous elements and attributes are stripped while all safe, standard HTML is preserved.

How the preview works

The page parses Markdown with marked using GitHub Flavored Markdown support and soft line breaks disabled, then sanitizes the generated HTML with DOMPurify before it is displayed or copied. This keeps the preview close to common GitHub-style rendering while removing unsafe markup from raw HTML in the source. Parsing, previewing, copying, and downloads all happen in your browser.

Difference between this tool and the full Markdown Editor

This tool stays focused on a quick paste-to-preview workflow, with direct Markdown and HTML copy and downloads. The full Markdown Editor is already available for longer writing sessions, with formatting shortcuts, local multi-document autosave, and Markdown/HTML import and export.

Paste from clipboard tips

Copying text from a word processor (Microsoft Word, Google Docs) and pasting it here will produce plain text - the bold, headings, and italics from the word processor will not transfer automatically, because Markdown is plain-text markup. To get formatted output, you need to add the Markdown syntax yourself (e.g., **bold**, # Heading).

Similarly, copying a formatted email and pasting it produces stripped plain text. If you want to convert rich-text HTML to Markdown first, use a dedicated HTML-to-Markdown converter.

Markdown beyond developers

Markdown is no longer just a developer tool - it is now the default writing format in many widely used platforms:

• GitHub / GitLab: READMEs, issues, pull requests, and wikis all render Markdown.
• Notion: supports Markdown shortcuts (type # for a heading, ** for bold).
• Slack: uses a subset of Markdown for bold, italic, code, and strikethrough in messages.
• Discord: supports bold, italic, underline, code blocks, and spoiler tags using Markdown-like syntax.
• Stack Overflow / Reddit: both use CommonMark or Markdown-like formatting in posts.

Learning the basics of Markdown pays dividends across dozens of platforms - it is quickly becoming the universal writing layer of the web.