Performance difference between 4.x and 5.x plugin

Hello @kpbryce132,

From a performance perspective, version 5.x introduced several important improvements, not limited to:

• Can work independently of Cloudflare – Caching is no longer Cloudflare-only, and the static cache works by itself if you want to use it, reliably on any hosting environment.
• Improved cache efficiency – Smarter handling of query parameters, cookies, AJAX requests, and purge logic helps increase cache hit rates and reduce server load.
• Smarter lazy loading – We’ve added a system that detects image placement making above-the-fold images load immediately while below-the-fold content loads lazily for faster perceived performance.
• Font optimization – Added some option to combine and locally host Google Fonts to reduce external requests.
• Database optimization tools – Clean up revisions, drafts, spam, and transients to keep the database lean.
• More reliable background processing – Improved scheduling and cache preloading stability.

Overall, versions from 5.0.0 onwards deliver better cache reliability, improved efficiency, and broader compatibility compared to 4. You can see a full changelog here.

The Pro version further enhances performance with advanced CSS and JavaScript optimization, including critical CSS generation for even better Core Web Vitals.

I hope this sheds some light on the differences. Have a great day ahead!

Hi,

That is a great question. Because performance depends heavily on your specific hosting environment, theme complexity, and existing site weight, we don’t quote a single percentage for the upgrade.

However, we can look at the efficiency gains in how the 5.x architecture handles data:

• Cache Hit Ratio: For many users, the smarter query parameter and cookie handling in 5.x results in a 10–15% increase in cache hit rates. This means more users are served static files instead of hitting your database.
• LCP (Largest Contentful Paint): Thanks to the new ‘above-the-fold’ detection for lazy loading, we often see a measurable reduction in LCP (sometimes by several hundred milliseconds) because critical images are no longer being delayed by generic lazy-load scripts.
• Reduced Server Overhead: By moving to a more stable background processing engine, the CPU spikes during cache preloading are significantly lower compared to the 4.x series.

In short, while we can’t promise a fixed percentage for every site, the 5.x version is designed specifically to move the needle on Core Web Vitals—specifically LCP and CLS—where 4.x was more limited.

Kind regards!