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HTML Formatter
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HTML Validator

Check your HTML for structural errors, unclosed tags, missing attributes, and common markup mistakes — instantly, in your browser.

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Validation Report

Run the validator to see your report here.

Status
Errors
Warnings

What it checks

Detects unclosed tags, missing doctypes, incorrect nesting, deprecated elements, missing alt attributes on images, and other common markup mistakes.

Browser-based

Validation runs entirely in your browser using the built-in HTML parser. No code is sent to any external server.

Fix then format

After fixing errors flagged here, use the HTML Formatter to clean up indentation and make the code readable.