Markdown Sanitizer

Markdown Sanitizer

Remove potentially dangerous HTML from Markdown content. Strip XSS attack vectors, malicious scripts, and unsafe elements while preserving safe formatting. Powered by DOMPurify.

markdown
sanitizer
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Quick Presets
Sample markdown with potentially malicious HTML
Input
Paste markdown that may contain unsafe HTML
How it works: Removes potentially dangerous HTML from markdown content. Strips script tags, event handlers (onclick, onerror), iframes, and other XSS attack vectors while preserving safe formatting. Powered by DOMPurify.

Complete Guide: Markdown Sanitizer

Everything you need to know about using this tool effectively

What is Markdown Sanitizer?

The Markdown Sanitizer strips potentially dangerous content from Markdown text. It removes HTML script tags, event handlers (onclick, onerror), iframe tags, and other elements that could execute JavaScript. The sanitized output is safe for rendering on a web page. All processing happens in the browser.

This tool uses a DOM-based sanitizer to parse Markdown-rendered HTML and remove dangerous elements and attributes. It keeps safe HTML tags (headings, paragraphs, links, images, lists, code) while stripping scripts, iframes, and event handlers.

Key Features
Removes script tags and event handlers
Removes iframe and object tags
Preserves safe HTML elements
Configurable allowed tags
Shows what was removed
Copy sanitized output to clipboard
Runs in the browser with no uploads
DOM-based sanitization
Common Use Cases
When and why you might need this tool

Processing user-submitted comments

Sanitize Markdown from user comments before rendering on a web page to prevent XSS attacks.

Rendering wiki content safely

Strip unsafe HTML from wiki pages submitted by users.

Preparing content for display

Sanitize Markdown before embedding it in a web page or email.

Auditing content security

Check Markdown for potentially malicious content before publishing.

How to Use This Tool
Step-by-step guide to get the best results
1

Paste Markdown

Enter Markdown that may contain unsafe HTML.

2

Sanitize

Click Sanitize. The tool removes dangerous content.

3

Review what was removed

Check the report of what was stripped.

4

Copy the safe output

Copy the sanitized Markdown for rendering.

Pro Tips
1

Always sanitize user-submitted Markdown before rendering it on a web page.

2

The tool removes <script>, <iframe>, <object>, and event handler attributes.

3

Safe HTML tags like <p>, <a>, <img>, <strong>, <em> are preserved.

4

For production use, integrate a dedicated sanitization library like DOMPurify.

Frequently Asked Questions
What is removed?

Script tags, iframe and object tags, event handler attributes (onclick, onerror, etc.), javascript: URLs, and other potentially dangerous content.

Is my content sent to a server?

No. All sanitization happens in your browser. Nothing is transmitted.

What HTML is preserved?

Safe tags including headings, paragraphs, links, images, lists, code blocks, tables, and basic formatting tags.

Can I configure allowed tags?

Yes. The tool lets you add or remove tags from the allowed list.

Is this enough for production?

For production, use a dedicated library like DOMPurify with server-side sanitization. This tool is useful for quick checks and development.