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What are some effective ways to reduce render-blocking JavaScript on my site?
Asked on Jan 30, 2026
Answer
Reducing render-blocking JavaScript is crucial for improving page load times and enhancing user experience. This can be achieved by deferring or asynchronously loading scripts, which allows the browser to render the page without waiting for JavaScript execution.
<!-- BEGIN COPY / PASTE -->
<script src="example.js" defer></script>
<script src="example.js" async></script>
<!-- END COPY / PASTE -->Additional Comment:
- Use the "defer" attribute to load scripts in order while not blocking HTML parsing.
- The "async" attribute loads scripts as soon as they are available, potentially out of order, but without blocking rendering.
- Consider inlining critical scripts that are small and necessary for initial rendering.
- Evaluate third-party scripts and load them asynchronously if possible.
- Use tools like Google Lighthouse to identify render-blocking resources.
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