Why is my WordPress site so slow?

Short answer: most slow WordPress sites are slow for the same handful of reasons: a heavy theme or page builder, too many plugins, images uploaded far bigger than they need to be, cheap shared hosting, an old version of PHP, and no caching. You can check most of them yourself in twenty minutes. The usual fix isn't a new site. It's removing what's weighing the current one down.

Speed matters more than most owners think. Most local searches happen on a phone, often on mobile data, and people don't wait. Google uses page experience as part of how it ranks pages, and its Core Web Vitals suggest the main content of a page should appear within about 2.5 seconds.

A slow site doesn't show you an error. It shows you fewer enquiries.

First, measure it

Run your homepage and your busiest service page through PageSpeed Insights. Look at the mobile result, not desktop. If there's a "Discover what your real users are experiencing" section with data in it, that's from real visitors and matters more than the lab score.

The usual suspects

1. A heavy theme or page builder. Multipurpose themes and drag-and-drop builders load code for every feature, whether you use it or not. This is the most common cause, and the hardest to fix without rebuilding the pages.
2. Too many plugins. It's not the number, it's what they do. Sliders, social feeds, chat widgets and "all-in-one" plugins that load scripts on every page are the worst offenders.
3. Huge images. A photo straight off a phone can be 4 or 5MB. On a web page it rarely needs to be more than a tenth of that.
4. Cheap hosting. Budget shared hosting puts hundreds of sites on one server. When a neighbour gets busy, your site slows down.
5. An old PHP version. Newer versions of PHP run WordPress noticeably faster. Your host's control panel will show which you're on.
6. No caching. Without it, WordPress rebuilds every page from scratch for every visitor.

What you can do yourself

• Delete plugins you're not using, not just deactivate them
• Compress and resize your biggest images before uploading
• Ask your host to move you to a current PHP version
• Turn on the caching your host provides, or one well-regarded caching plugin
• Remove sliders, autoplay video and social feeds from the homepage

Take a backup before you change anything, and test the site afterwards, especially forms.

When to get help

If you've done the basics and the mobile score is still poor, the problem is usually the theme or page builder itself, or something deeper in how the site was built. That's when a proper speed fix, or sometimes a rebuild, makes more sense than another plugin. Read how a slow page costs you the deal for what's at stake.

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