HTML Validator
Validate your HTML code with client-side parsing checks and error detection.
What is HTML Validator?
HTML Validator is a comprehensive web development tool that analyzes HTML code for syntax errors, structural issues, and best practices violations. It performs client-side validation to identify problems that could affect website functionality, accessibility, and SEO performance.
This tool checks for common HTML issues including unclosed tags, missing DOCTYPE declarations, improper nesting, and structural problems. It provides detailed error reports with line numbers and suggestions for fixes, making it essential for web developers, designers, and content creators.
Whether you're debugging website issues, ensuring code quality, preparing for deployment, or learning HTML best practices, this validator helps you create clean, standards-compliant HTML that works consistently across all browsers and devices.
What Problems Does It Solve?
Syntax Errors
Identifies unclosed tags, missing attributes, and malformed HTML that can cause rendering issues and browser compatibility problems.
Standards Compliance
Ensures HTML code follows W3C standards and best practices for better cross-browser compatibility and future-proofing.
SEO Optimization
Helps identify HTML issues that could negatively impact search engine crawling and indexing of your website.
Accessibility Issues
Detects structural problems that could affect screen readers and other assistive technologies used by users with disabilities.
How to Use HTML Validator
Paste HTML Code
Copy and paste your HTML code into the textarea on the left side. You can paste complete HTML documents or HTML fragments.
Review Validation Results
Check the validation results panel on the right to see any errors, warnings, or issues found in your HTML code.
Fix Issues
Use the error messages and line numbers to identify and fix HTML issues. The tool also provides HTML statistics for analysis.
HTML Validation Best Practices:
- • Always include a DOCTYPE declaration at the beginning of your HTML documents
- • Ensure all tags are properly closed and nested correctly
- • Use semantic HTML elements (header, nav, main, section, article, footer) for better structure
- • Include alt attributes for images and proper heading hierarchy (h1, h2, h3, etc.)
- • Validate your HTML regularly during development to catch issues early
- • Test your validated HTML across different browsers to ensure compatibility
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