HTML & CSS Version Checker
Analyze your website's HTML and CSS versions, feature support, and compatibility with modern web standards.
Understanding Web Standards
Modern web development relies on following established standards to ensure compatibility, accessibility, and performance.
HTML Standards
HTML5
The current standard with rich semantic elements and multimedia support
Semantic Elements
Improve accessibility and SEO with meaningful structure
Form Features
Modern input types and validation for better user experience
CSS Features
Modern Layout
Flexbox and Grid for responsive designs
Animations & Transitions
Smooth visual effects for better interactivity
Custom Properties
Variables for maintainable styling
Best Practices
- Keep your DOCTYPE declaration current
- Use semantic HTML elements appropriately
- Implement modern CSS features when possible
- Include proper meta tags for SEO
- Test across different browsers
Browser Support
Modern features are well-supported across current browsers. However, if you need to support older browsers, consider:
- Progressive enhancement strategies
- Fallback styles for older browsers
- Feature detection using @supports
- Polyfills for critical features
Comprehensive Analysis
Analyze your website's compatibility with modern web standards and features.
HTML Version Detection
Detect HTML version and doctype with semantic element analysis.
CSS Analysis
Analyze CSS versions and modern feature usage across stylesheets.
Feature Support
Check for modern web features and browser compatibility.
Deep Analysis
Comprehensive scanning of external resources and dependencies.
Issue Detection
Identify potential compatibility issues and outdated features.
Meta Information
Extract and analyze meta tags and document structure.
How to Use the Version Checker
Follow these easy steps to get started with Version Checker and achieve your goals quickly.
Enter the website URL you want to analyze
Get detailed analysis of HTML and CSS versions
Review feature support and compatibility
Get recommendations for improvements
Version Checker FAQ
Find answers to commonly asked questions about our tools and services.
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