How can I reduce JavaScript execution time to improve my site's interactivity?

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How can I reduce JavaScript execution time to improve my site's interactivity?

Asked on Dec 23, 2025

Answer

Reducing JavaScript execution time is crucial for improving a site's interactivity, as it directly impacts the First Input Delay (FID) metric. Optimizing JavaScript can help ensure that the main thread is free to respond to user interactions promptly.

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

Additional Comment:

Use "async" or "defer" attributes on script tags to prevent blocking the main thread during page load.
Minimize and compress JavaScript files to reduce their size and execution time.
Consider code splitting to load only necessary JavaScript for each page.
Identify and remove unused JavaScript using tools like Chrome DevTools.
Leverage web workers to offload heavy computations from the main thread.

✅ Answered with Core Web Vitals best practices.

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

How can I reduce JavaScript execution time to improve my site's interactivity?

Asked on Dec 23, 2025

Answer

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