Why is my WordPress site slow?
The usual causes, how to check which ones apply to your site, what fixes them, and when moving to a new site works out cheaper than fixing the old one.
By Gary Blake · Bath IT, Radstock
Guides
WordPress
A slow WordPress site is nearly always down to a handful of things: a heavy page builder, too many plugins, images that are far too big, cheap hosting, no caching, or an old version of PHP. Most of them can be fixed. Find out which apply to you first, because the right fix depends on the cause, and sometimes a new site is cheaper than fixing the old one.
Why it matters
A slow site loses people before they've read a word, especially on a phone with a weak signal. Google takes page speed into account too, so a slow site can rank below a faster competitor. And if the admin feels slow to you, the site is often slow for your visitors as well.
The usual causes
Page builders. Tools like Elementor, Divi and WPBakery make WordPress easy to design with, but they add a lot of code to every page. A simple page of text and photos can end up far heavier than it needs to be.
Too many plugins. Every plugin can add its own scripts, styles and database work. Some load on every page whether they're needed or not, and sites that have been added to for years often have several plugins doing the same job.
Big images. A photo straight off a phone or camera is far bigger than any screen needs. Upload it as it is and every visitor downloads the full-size file.
Cheap hosting. Low-cost shared hosting puts a lot of sites on one server. When the server is busy, your site waits its turn.
No caching. Without caching, WordPress builds each page from scratch for every visitor. With it, the finished page is kept ready and sent straight away.
An old version of PHP. Newer versions of PHP are faster as well as safer. Plenty of sites stay on old ones because nobody has checked whether the theme and plugins would cope with an upgrade.
How to check
Start with our free SEO check. It looks at your site's speed alongside the other basics Google cares about, and tells you what to fix in plain English.
Google's PageSpeed Insights is free too. Put in your address and it scores the page on mobile and desktop and lists what's slowing it down. Look at the mobile result, because that's where sites usually struggle, and test a busy inner page as well as the homepage.
Then look in your hosting control panel for the PHP version, and count your plugins. If you can't say what half of them do, that's a finding in itself.
The fixes
Resize and compress images, and set the site to do it for new uploads.
Turn on caching, through your host or a well-maintained caching plugin.
Remove plugins you don't need, and swap heavy ones for lighter ones.
Upgrade PHP to a supported version, after testing that the site still works.
Move to better hosting if the server itself is the bottleneck.
Images and caching are often the quickest wins. Plugins and PHP need more care, because changing them can break things, so try them on a copy of the site first, not the live one.
When the page builder is the problem
Some sites stay slow after all of that, because the page builder itself is the weight. You can't remove it without rebuilding every page it made. At that point the honest comparison is between rebuilding in WordPress without the builder, and moving to something else.
If the site needs rebuilding anyway, moving can be the cheaper route. Bath IT's own sites start at £495 for 5 pages, and moving your existing content and redirecting the old addresses adds £300. Our guide to whether to move off WordPress covers when that makes sense, and when it doesn't.
Getting help
We speed up WordPress sites as well as moving people off them, and we'll tell you which is better value for yours. Work is quoted in writing first, at £75 an hour. See WordPress help for how it works.
Quick answers
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We'll build a free mockup of your homepage on our own platform, so you can compare it with what you have now before you decide anything.