Why Is My Site Slow? A 10-Minute Diagnosis

Slowness has four usual suspects. Work through them in order — the first two account for most of the pain on typical WordPress sites.

1. Server response time (TTFB)

Before your page can render anything, the server has to produce the HTML. On overloaded shared hosting this alone can take 1–2 seconds. Test: run your site through PageSpeed Insights and look for "Reduce initial server response time". If TTFB is over ~600 ms, hosting is your biggest lever — see our managed hosting comparison.

2. No page caching

WordPress builds every page from PHP and database queries unless something caches the result. Managed hosts do this at the server level; on other hosting, install a caching plugin and verify it works (repeat visits should be dramatically faster).

3. Heavy images

The most common Largest Contentful Paint (LCP) killer. Compress images, size them to their displayed dimensions, and serve WebP/AVIF. This is free and often cuts seconds.

4. Plugin & theme bloat

Every active plugin adds PHP work and often extra scripts. Deactivate what you don't use, and test a lightweight theme on staging if your theme loads multiple render-blocking bundles.

Measure, change one thing, measure again

Use the same tool for every measurement (PageSpeed Insights, or a mobile app that wraps it) and change one variable at a time — otherwise you won't know what worked. Our Core Web Vitals guide explains what each number means.

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