HTML Validator
Validate HTML markup and check for common issues. Detect missing attributes, accessibility problems, deprecated tags, and structure errors. Free and runs entirely in your browser.
How to Use HTML Validator
How to Use HTML Validator
Step 1: Enter Your HTML
Paste or type your HTML content into the editor. The tool validates in real-time as you type.
Step 2: View Validation Results
The validator checks for:
- Document Structure - DOCTYPE, html, head, body tags
- Meta Information - charset, viewport, title
- Accessibility - alt attributes, form labels, lang attribute
- Best Practices - deprecated tags, external link security
- SEO Basics - heading hierarchy, title tag
Step 3: Review Issues
Issues are categorized by severity:
- Errors - Critical problems that must be fixed
- Warnings - Important issues that should be addressed
- Suggestions - Recommendations for improvement
Step 4: Check Statistics
View detailed statistics about your HTML:
- Total elements and tag counts
- Images and alt attribute coverage
- Links (internal vs external)
- Form elements and inputs
- Heading structure (H1-H6)
Use Cases
- Validate HTML before deployment
- Check accessibility compliance
- Find missing image alt attributes
- Verify document structure
- Debug rendering issues
Frequently Asked Questions
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