What is HTML Sanitizer?
HTML Sanitizer removes potentially dangerous elements and attributes from HTML to prevent XSS (Cross-Site Scripting) attacks. When displaying user-generated HTML, you must sanitize it to remove script tags, event handlers, and javascript: URLs that could execute malicious code. HTML Sanitizer provides configurable sanitization with allowlists for safe tags and attributes.
Why Use This Tool?
Displaying user-generated content (comments, posts, rich text) requires careful sanitization to prevent XSS attacks. Common dangerous elements include: script tags, onclick handlers, javascript: URLs, iframe embeds, and style-based attacks. HTML Sanitizer removes these threats while preserving safe formatting. It processes locally, which is important when testing with actual user content.
How to Use HTML Sanitizer
- Paste HTML content to sanitize
- Select a preset: strict (text only), basic (formatting), rich (most tags)
- Or configure custom allowlists for tags and attributes
- Click "Sanitize" to clean the HTML
- Preview the safe output and view removed elements
- Copy sanitized HTML for use in your application
Features
- Preset security profiles: strict, basic, rich, custom
- Configurable tag allowlists
- Attribute filtering per tag
- javascript: URL removal
- Event handler attribute stripping (onclick, onerror, etc.)
- Style attribute sanitization
- Preview mode to test sanitized output
- Report of removed dangerous elements
Common Use Cases
- User Content: Sanitize comments and forum posts
- Rich Text Editors: Clean WYSIWYG editor output
- Email Display: Safely render HTML emails
- CMS: Process user-submitted HTML content
- API Security: Validate HTML before database storage
Tips & Best Practices
- ✓ Use the strictest preset that meets your needs
- ✓ Even "safe" tags like img can have malicious onerror handlers
- ✓ CSP (Content Security Policy) provides additional protection layer
- ✓ Test sanitization with known XSS payloads from OWASP
How It Compares to Alternatives
DOMPurify is the standard library for HTML sanitization in JavaScript. HTML Sanitizer provides a visual interface for testing and configuring sanitization rules. Unlike regex-based sanitizers, it uses proper HTML parsing that understands nested structures and edge cases.
Frequently Asked Questions
What is HTML sanitization?
HTML sanitization removes potentially dangerous elements and attributes from HTML to prevent XSS (Cross-Site Scripting) attacks. Essential when displaying user-generated content.
What tags are removed by default?
We remove script, iframe, object, embed, form, and style tags. Event handlers (onclick, onerror, etc.) and javascript: URLs are also stripped. Customize allowed tags in settings.
Can I allow some HTML tags?
Yes! Configure an allowlist of safe tags (like p, a, img, strong) and attributes. Our preset profiles include "Basic" (text only), "Rich Text" (formatting), and "Full" (most tags).
Ready to Get Started?
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