Glossary

Critical CSS

The minimum CSS required to render above-the-fold content, typically inlined in the HTML head for faster rendering.

What is Critical CSS?

Critical CSS is the minimum CSS needed to render above-the-fold content. Inlining it in HTML eliminates render-blocking CSS requests, improving FCP and LCP.

Key Takeaways

1.Critical CSS is important for website performance and SEO.
2.You can measure it using tools like BulkAudit and Google Lighthouse.
3.Improving this metric can lead to better user experience and search rankings.

Learn More

Google Web Fundamentals

Related Terms

Responsive Web Design

Related Guides

Critical CSS - Inline Above-the-Fold Styles
Resource Hints Guide - Preload, Prefetch, Preconnect
Web Caching Strategies for Performance

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