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How can I optimize my site's critical CSS to improve rendering speed?
Asked on Jan 21, 2026
Answer
Optimizing your site's critical CSS is essential for improving rendering speed by ensuring that the most important styles are loaded first. This can significantly enhance the First Contentful Paint (FCP) and Largest Contentful Paint (LCP) metrics.
Example Concept: Critical CSS refers to the minimal set of CSS rules required to render the above-the-fold content of a webpage. By inlining this CSS directly into the HTML document's
, you reduce render-blocking resources and improve initial load times. The rest of the CSS can be loaded asynchronously to ensure the full page is styled correctly after the initial render.Additional Comment:
- Identify critical CSS using tools like Chrome DevTools or online generators.
- Inline the critical CSS within the section of your HTML to prioritize its loading.
- Load the remaining CSS asynchronously using the "media" attribute or JavaScript.
- Regularly update your critical CSS as your design changes to maintain performance.
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