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How can I reduce JavaScript execution time to improve page load speed?
Asked on Feb 15, 2026
Answer
Reducing JavaScript execution time is crucial for improving page load speed and enhancing user experience. By optimizing how JavaScript is loaded and executed, you can significantly improve metrics like First Input Delay (FID) and Total Blocking Time (TBT).
<!-- BEGIN COPY / PASTE -->
<script src="example.js" async></script>
<!-- END COPY / PASTE -->Additional Comment:
- Use "async" or "defer" attributes to load scripts without blocking the HTML parser.
- Minify and compress JavaScript files to reduce their size.
- Identify and remove unused JavaScript with tools like Lighthouse or Chrome DevTools.
- Consider code splitting to load only necessary JavaScript for the initial page view.
- Utilize web workers for offloading heavy computations from the main thread.
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