How can I reduce JavaScript execution time on mobile devices?

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How can I reduce JavaScript execution time on mobile devices?

Asked on Jan 08, 2026

Answer

Reducing JavaScript execution time on mobile devices is crucial for improving performance and user experience. This can be achieved by optimizing scripts, deferring non-critical JavaScript, and minimizing the amount of JavaScript loaded initially.

Example Concept: Minimize JavaScript execution time by splitting large scripts into smaller, asynchronous chunks. Use "async" or "defer" attributes for non-critical scripts to prevent them from blocking the initial page load. Additionally, consider tree-shaking to remove unused code and code-splitting to load only what is necessary for the initial view.

Additional Comment:

Use code-splitting techniques to load JavaScript only when needed.
Implement lazy loading for scripts that are not required immediately.
Consider using a service worker to cache scripts for offline use and faster repeat visits.
Regularly audit your JavaScript bundle size and remove any unnecessary libraries or polyfills.
Utilize tools like Webpack or Rollup to optimize and bundle your JavaScript efficiently.

✅ Answered with Core Web Vitals best practices.

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