Validators
HTML Validator
Validate your HTML markup to identify missing tags, unclosed elements, and syntax errors instantly. This tool provides real-time feedback with precise line numbers to help you create clean, standards-compliant web pages.
Validate your HTML markup to identify missing tags, unclosed elements, and syntax errors instantly. This tool provides real-time feedback with precise line numbers to help you create clean, standards-compliant web pages.
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Tip
Always include a lang attribute in your html tag for better accessibility and SEO.
Best Practice
Use a validator regularly during development to catch nesting errors before they break your CSS.
Did You Know?
Valid HTML is a prerequisite for consistent performance across different mobile and desktop browsers.
Q: Why should I validate my HTML? A: Validation ensures your code follows web standards, which leads to better browser compatibility and fewer rendering issues.
Q: Can this tool fix my HTML automatically? A: This tool identifies errors for you to fix. For automatic formatting, you can use our HTML Formatter tool.
Q: Does it support HTML5? A: Yes, the validator is designed to handle modern HTML5 standards including all new semantic elements.
Tip
Check for duplicate IDs which can cause unpredictable behavior in JavaScript and CSS selectors.