How can I effectively optimize my site's JavaScript execution for better performance?

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How can I effectively optimize my site's JavaScript execution for better performance?

Asked on Jan 05, 2026

Answer

Optimizing JavaScript execution is crucial for improving site performance and enhancing user experience. By minimizing and deferring JavaScript, you can reduce the time it takes for your site to become interactive.

<!-- BEGIN COPY / PASTE -->
    <script src="script.js" defer></script>
    <script src="another-script.js" async></script>
    <!-- END COPY / PASTE -->

Additional Comment:

Use "defer" to load scripts in the order they appear, ensuring they execute after the HTML is parsed.
Use "async" for scripts that can be executed independently of other scripts, reducing blocking time.
Minify JavaScript files to decrease file size and improve load times.
Consider code splitting and lazy loading to only load JavaScript when needed.
Analyze and remove unused JavaScript to reduce execution time.

✅ Answered with Core Web Vitals best practices.

Ask any question about Performance here... and get an instant response.

How can I effectively optimize my site's JavaScript execution for better performance?

Asked on Jan 05, 2026

Answer

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