My website audit highlights unused CSS and scripts — should I remove them?

From an SEO point of view, I don't usually treat unused CSS and JavaScript as a direct ranking factor. Instead, I focus on the impact they have on page speed, Core Web Vitals, and user experience. Large amounts of unused code increase file sizes, require additional browser processing, and can delay rendering and interactivity, which may negatively affect metrics such as LCP, FCP, and Total Blocking Time.

My usual process is:

• Run the website through Google PageSpeed Insights and Lighthouse to identify the largest unused CSS and JavaScript files.
• Audit themes, plugins, third-party scripts, and tracking tools that load globally across the website.
• Load CSS and JavaScript only on pages where they are actually needed.
• Defer or delay non-critical JavaScript.
• Generate critical CSS for above-the-fold content and load remaining styles asynchronously.
• Remove outdated plugins, widgets, and libraries that are no longer being used.

One thing I've learned is that chasing a perfect PageSpeed score isn't always the goal. Many modern websites will still have some unused CSS because themes, plugins, and dynamic elements require code that isn't used on every page. The objective should be reducing unnecessary bloat without breaking functionality.

In short, focus on improving real-world performance rather than achieving a perfect Lighthouse score. Faster pages, better Core Web Vitals, and a smoother user experience will usually deliver more SEO value than eliminating every unused CSS or JavaScript warning.

I have come across this issue quite a few times while working with clients here in Dubai. As an SEO Analyst and SEO content writer, this might seem like a simple technical warning at first, but there is usually more to it than what website audit tools show.

Unused CSS and JavaScript files can definitely affect page speed and overall website performance, especially on mobile devices. However, I never advise clients to remove those files immediately without checking how the website actually uses them. Many websites today rely on themes, plugins, tracking tools, animations, booking systems, or ecommerce features that load scripts across different pages. A file may appear unused on one page but still be important for another section or user interaction.

Instead of blindly deleting files, I prefer analyzing which resources are genuinely unnecessary and which ones can be optimized safely. In many cases, minifying files, delaying non-critical scripts, reducing plugin overload, and loading assets only where needed can improve performance significantly without breaking the website.

From an SEO standpoint, speed and user experience matter a lot, but functionality matters just as much. A website that loads quickly but has broken elements or poor usability will still struggle to perform well in search results and user engagement.

Yes, I usually review and remove unused CSS and scripts whenever possible. I’ve seen that unnecessary files can slow down a website and affect both user experience and SEO performance. But before removing anything, I always test the website carefully to make sure those files are not linked to important functions or plugins. In my experience, reducing unused CSS and JavaScript helps improve page speed and overall website performance.