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Home/Tools/HTML Tools/HTML Structure Validator

HTML Structure Validator

Validate HTML structure online. Check for unclosed tags, mismatched elements and common HTML errors. Browser-based — your code never sent to any server.

Your data never leaves your browser

Related

HTML Formatter & Beautifier

Format and beautify HTML with proper indentation

HTML Escape / Unescape

Escape and unescape HTML special characters

HTML Tag Stripper

Remove HTML tags and extract plain text

Frequently Asked Questions

What does this validator check?

Unclosed tags, mismatched nesting, void element issues (img without src alt, etc.) and basic structural problems. For full W3C validation, use the official W3C validator.