Edit Markdown, preview sanitized HTML in real time and copy Markdown or HTML.
The Markdown Viewer shows, in real time, how your Markdown text turns into HTML. You write in the editor and the preview beside it is rendered with the marked parser in GitHub Flavored Markdown (GFM) mode, which understands headings, lists, emphasis, links, images, code blocks, tables, task lists and more. Before it appears, the HTML passes through DOMPurify, which removes scripts, event handlers and other dangerous constructs, that's why the preview is sanitized and safe even with content pasted from third parties. There are ready-made templates (README, documentation, changelog, pull request and blog), split/editor/preview view modes, fullscreen and document statistics (characters, words, lines, headings, links, images, code blocks and reading time). You can copy the Markdown, copy the HTML or download a complete .html file, all processed locally, with the content never sent to servers.
The text is converted by the marked parser configured in GitHub Flavored Markdown (GFM). Beyond the core (headings with #, lists, **bold**, *italic*, links, images and code blocks with backticks), GFM adds tables, task lists (- [ ] and - [x]), strikethrough and autolinks. Automatic line breaking is turned off, so a single newline does not become a <br>; use a blank line to separate paragraphs.
After conversion, the HTML passes through DOMPurify before being displayed. This means dangerous tags and attributes, such as <script> and onclick event handlers, are removed, so the preview reflects the content's structure without executing code. That is what makes it safe to preview Markdown coming from external sources.
Example 1, basic syntax: # Title becomes <h1>Title</h1>; **important** becomes <strong>important</strong>; and a list written with "- item" and "- other" becomes a <ul> with two <li>. A GFM table with | Column | and the dash row becomes a <table> with a header.
Example 2, sanitization: if you paste <script>alert(1)</script> alongside the Markdown, the preview does not run the alert, DOMPurify removes the tag before display. The same applies to attributes like onerror on images, which are dropped, keeping only safe markup.
The viewer is useful for writing and reviewing README files, documentation, changelogs, pull request descriptions and posts, checking the formatting before publishing. The templates give a starting point, and HTML export lets you reuse the content in other contexts; the download already includes a basic, readable style.
About the limits: the result follows the GFM rules implemented by marked, which can differ from other renderers (GitHub, GitLab, a specific CMS), so the same Markdown may vary across platforms. And, for safety, embedded HTML with scripts or dangerous attributes is sanitized, great for preview, but it means effects that depend on scripts will not work here.
Paste the code into your HTML and the tool shows up on your page, without J-Kit's navigation and ads. It still runs in the browser of whoever visits your site.
<iframe
src="https://jkit.tools/embed/en-US/markdown-viewer"
width="100%"
height="600"
style="border:0"
loading="lazy"
title="Markdown Viewer"
></iframe>These references help contextualize formulas, standards, APIs and limitations used on this page. They do not replace professional validation when a result has legal, financial, medical or operational impact.
Yes. You write Markdown in the editor and see the rendered, sanitized HTML update in real time beside it. You can copy the Markdown, copy the generated HTML or download a complete .html file, and also track statistics such as heading, link and image counts and reading time.
A clean Markdown preview for J-Kit.
const safe = true;
Markdown and rendered HTML stay in your browser. The preview is sanitized with DOMPurify.