HTML Validity Check by W3C Standards
Free HTML code validator: check for errors and compliance with W3C standards. Improve quality and cross-browser compatibility.
Website HTML code error checking. Validator analyzes syntax and W3C standards, helping optimize markup.
Questions and Answers
All about HTML checking with W3C: why validation is important and what errors may occur
What is W3C HTML validation?
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W3C validation is checking the site's HTML code for compliance with the World Wide Web Consortium W3C standards. It helps identify syntax errors and improve markup quality.
Why check HTML code for validity?
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Valid HTML guarantees correct site display in different browsers and devices, improves accessibility and reduces the likelihood of development errors.
Does HTML validity affect SEO?
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Directly — no. But indirectly, valid code speeds up site loading, improves user convenience and reduces the likelihood of errors, which positively affects SEO.
What errors can an HTML validator find?
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Main errors: unclosed or extra tags, invalid attributes, ID duplication, incorrect element nesting, deprecated tags.
What does the HTML checking service show?
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The service displays a list of errors and warnings in the code, indicating the lines where they occur, as well as recommendations for their correction.
Can you check the entire site or just a page?
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The validator checks a specific HTML document. To check the entire site, you need to run several pages separately.
Is the HTML checking service free?
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Yes, HTML code checking is available online for free and does not require registration.
How often should you check HTML for validity?
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It is recommended to perform a check after a site redesign, changes to templates, or before launching new pages.
1. Remove unnecessary and deprecated tags
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Get rid of deprecated tags and unnecessary elements to keep the code clean and correct.
2. Monitor correct nesting
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Check that tags are properly nested: headers, lists, tables and blocks must follow the HTML structure.
3. Close all tags
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Every open tag must be closed. This is important for correct page display in all browsers.
4. Use valid attributes
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Check tag attributes: they must comply with HTML5 standards and be correct for the specific tag.
5. Minimize ID duplication
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Each identifier (id) on the page must be unique to avoid conflicts in scripts and styles.
6. Optimize comments and spaces
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Remove unnecessary comments and unnecessary spaces to reduce HTML size and speed up loading.
7. Check HTML through W3C validator
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Regularly use HTML validation services to identify errors and keep site code in accordance with standards.
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