HTML Validator
Paste HTML markup to check for unclosed tags, deprecated elements, and accessibility issues.
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We will check for syntax errors, unclosed tags, and best practices
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HTML Validation: The Complete Guide to Clean Markup
Learn how HTML validation works, why it matters for SEO and accessibility, and how to fix common markup errors.
What Is HTML Validation?
HTML validation checks whether your markup conforms to the HTML specification. Valid HTML ensures that browsers render your page consistently, assistive technologies can interpret your content correctly, and search engines can crawl your site without issues.
5 min readRead full guide