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  3. HTML Validator

HTML Validator

Validate HTML and check for errors

Related Tools

  • HTML Formatter - format valid HTML
  • XML Validator - validate XML
  • JSON Validator - validate JSON
  • CSS Formatter - format stylesheets

How to Use HTML Validator

  1. Paste your HTML

    Enter the HTML code you want to validate.

  2. Check validity

    See validation results with any errors or warnings explained.

  3. Fix errors

    Use the error messages to correct issues in your HTML.

Frequently Asked Questions

Is the HTML Validator free to use?
Yes, the HTML Validator is completely free with no limitations. Validate as many HTML documents as you need without any registration.
Is my HTML data private during validation?
Yes, all HTML validation happens locally in your browser. Your HTML code is never sent to any server, making it safe to validate pages with sensitive content or unreleased features.
What does the HTML Validator check for?
The validator checks for proper tag nesting, required attributes, deprecated elements, accessibility issues, and HTML5 compliance. It identifies errors and warnings that could cause rendering problems or accessibility barriers.
Why should I validate my HTML?
Valid HTML renders more consistently across browsers, is more accessible to screen readers, ranks better in search engines, and is easier to maintain. Validation catches errors that could cause layout issues or break functionality.
What is the difference between errors and warnings?
Errors indicate invalid HTML that violates the specification and may cause rendering problems. Warnings highlight deprecated elements, accessibility concerns, or best practice violations that should be addressed but will not break the page.