How can I optimize my site's JavaScript execution to improve load times?

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How can I optimize my site's JavaScript execution to improve load times?

Asked on Jan 14, 2026

Answer

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

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

Additional Comment:

Use "async" to load scripts asynchronously, allowing the page to continue parsing while the script loads.
Use "defer" to ensure scripts execute after the document has been parsed, improving render times.
Consider splitting large scripts into smaller, modular files to load only what's necessary for each page.
Utilize code-splitting and tree-shaking techniques to eliminate unused code.
Regularly audit your JavaScript with tools like Lighthouse to identify performance bottlenecks.

✅ Answered with Core Web Vitals best practices.

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

How can I optimize my site's JavaScript execution to improve load times?

Asked on Jan 14, 2026

Answer

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