My website is loading slowly-what to check
Diagnose the cause of a slow website: heavy plugins, missing caching, oversized images, resource limits, or network issues.
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Before changing anything, measure current performance. Tools like Google PageSpeed Insights and GTmetrix show exactly what's slow and how to fix it. Run a test first so you can compare before and after your changes.
Enable caching
An uncached WordPress or PHP site processes every page from scratch for every visitor. Caching stores pre-built pages so the server serves them instantly without running PHP or querying the database.
- WordPress-Install WP Rocket, W3 Total Cache, or LiteSpeed Cache
- Redis object cache-UnderHost includes Redis; install the Redis Object Cache plugin to connect WordPress to it
- Cloudflare-Enable proxying through Cloudflare for CDN and caching of static assets
Optimize images
Large images are the most common cause of slow page loads. A 5 MB hero image makes every page load 5 MB of data before anything else renders.
- Use WebP format (50% smaller than JPEG, same quality)
- Install ShortPixel or Smush to auto-compress images on upload
- Resize images to actual display dimensions-don't upload 4000px images for a 800px container
- Enable lazy loading (already on by default in WordPress 5.5+)
Identify slow plugins
Each plugin adds processing time. The Query Monitor plugin shows exactly how long each component takes to load, including database queries per plugin. Use it to identify the bottleneck, then:
- Deactivate plugins you don't use
- Replace heavy plugins with lighter alternatives
- Investigate plugins making excessive database queries
Update PHP version
PHP 8.x is significantly faster than PHP 7.x. If you're still on PHP 7.4, upgrading to 8.1 or 8.2 can noticeably speed up page generation. Change it in cPanel → MultiPHP Manager. Always test plugin compatibility after upgrading.
Resource limits
On shared hosting, CloudLinux limits CPU and memory per account to ensure fair usage. If your site consistently uses a lot of resources, it will be throttled. Check cPanel → Metrics → Resource Usage (if available on your plan). Signs of resource throttling:
- Site is slow at peak hours but fast at night
- Slow pages even with caching enabled
- Intermittent 508 errors (Resource Limit Is Reached)
If your site is legitimately outgrowing shared hosting, upgrading to a Cloud VPS gives you dedicated CPU and RAM.
Network speed test
Use the ping or traceroute command to test network latency to your server. High latency can cause slow response even when the server itself is fast. If you consistently see high latency, open a technical support ticket-our team can investigate from the network side.
Related: WordPress performance optimization | My website is down-what to check first | PHP settings in cPanel | Upgrade account
Still troubleshooting?
Use UnderHost tools for quick checks, or open a support ticket when the issue needs account or server access.
