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HTML Validator

Validate HTML code for errors, warnings, and best practices

What is HTML Validation?

HTML validation is the process of checking HTML code against the official HTML standards to identify errors, warnings, and potential issues. Valid HTML ensures your web pages work correctly across all browsers, improve SEO, and provide better accessibility for users with assistive technologies.

Our free HTML validator checks your code for syntax errors, deprecated elements, accessibility issues, and best practice violations. All validation happens in your browser, ensuring your code remains private.

Why Validate HTML?

  • Cross-Browser Compatibility: Ensures your code works in all browsers
  • SEO Benefits: Search engines prefer valid, well-structured HTML
  • Accessibility: Valid HTML improves screen reader compatibility
  • Error Prevention: Catch errors before they cause problems
  • Best Practices: Learn and follow HTML standards

HTML Code

Validation Results

Enter HTML code to validate

About HTML Validation

HTML validation helps ensure your code follows web standards, improves browser compatibility, and enhances accessibility. Valid HTML is easier to maintain and debug.

What We Check:

  • Unclosed or mismatched HTML tags
  • Missing DOCTYPE declaration
  • Missing essential tags (head, body)
  • Deprecated HTML tags
  • Missing alt attributes on images
  • HTML structure and syntax