WebValid

HTML Validation & Accessibility

Validate your HTML code against W3C standards to identify syntax errors, accessibility issues, and deprecated elements for better SEO and cross-browser compatibility

Why Validate HTML & Accessibility?

Valid HTML and WCAG compliance are the foundation of a professional web. Our tool checks for syntax errors that break parsers and accessibility issues that block screen readers—all in one pass

🔍 What We Check

  • Syntax errors (unclosed tags, malformed attributes)
  • Missing required attributes (alt, lang, meta charset)
  • Deprecated HTML elements (<font>, <center>)
  • WCAG contrast issues (text vs background)
  • Missing ARIA labels for interactive elements
  • Improper heading hierarchy (skipped levels)

Benefits of Valid Markup

  • Better SEO: Search engines rank clean HTML higher
  • Faster parsing: Browsers render valid code more efficiently
  • Accessibility: Screen readers rely on proper structure
  • Future-proof: Standards-compliant code ages better

💡 Pro Tip

Accessible HTML is also SEO-friendly HTML. Fixing contrast issues and missing ARIA labels improves your site for both users and search engines

Frequently Asked Questions

What is an HTML validator?

An HTML validator is a tool that checks your HTML code for syntax errors, W3C compliance issues, and accessibility problems. It ensures your website follows web standards and works correctly across all browsers

Why should I validate my HTML?

Validating HTML improves SEO rankings, ensures faster page loading, enhances accessibility for screen readers, and prevents cross-browser compatibility issues. Search engines like Google prioritize clean, valid markup

What HTML errors does this tool check for?

Our validator checks for: unclosed tags, malformed attributes, missing alt text on images, deprecated elements (font, center), WCAG contrast violations, missing ARIA labels, and improper heading hierarchy

How often should I validate my HTML?

Validate HTML after every major code change, before production deployments, and at least monthly for active websites. Automated CI/CD integration can validate on every commit

Complete Web Audit Workflow

01
CSS Audit
Analyze your stylesheets for performance bottlenecks and specificity issues
Learn more
02
JavaScript Audit
Deep scan for exposed secrets, API keys, and sensitive tokens in your code
Learn more
03
SEO Audit
Optimize titles, descriptions, and other critical search engine signals
Learn more