Why is my website slow? Causes and fixes

A slow website usually comes down to a few familiar causes: photos that are too large, too many or heavy plugins, slow hosting, or scripts from other companies. Don't guess. Measure first. Then you know where to start and whether you can fix it yourself. The tips below are mainly for WordPress sites.

Measure first: how to test your website's speed

Google has a free tool for testing how fast a page is: PageSpeed Insights.

1. Enter your website's address and run the test.
2. Look at the mobile results first. Many visitors come in on their phone, and the mobile test is stricter.
3. Test a few times, and not just your homepage but other important pages too.
4. Write down the results, with the date. That way you can compare later.

Two kinds of results

The score from 0 to 100. This is a lab test: PageSpeed loads your page once under fixed test conditions. For mobile, the test simulates an average phone on a slower connection, so that score is usually lower than on desktop. The score can vary a little from one run to the next, even if you haven't changed anything. According to Google's explanation of the score, 90 to 100 is good (green), 50 to 89 needs improvement (orange) and 0 to 49 is poor (red).

For comparison: the homepage of our own site, baswebdesign.com (not built in WordPress), scored 97 on mobile and 100 on desktop in PageSpeed Insights on 18 October 2026. That's a lab score too, and it can vary between runs.

Data from real visitors. At the top, you'll sometimes see an assessment based on real visitors using Chrome. That data only appears if your site has enough visitors. For many small sites it's missing. That's not an error; use the lab test instead.

The three Core Web Vitals in plain English

Google uses three measurements to judge how visitors experience your page: the Core Web Vitals. The thresholds below come from web.dev, Google's site for web developers.

• LCP (Largest Contentful Paint): how quickly the main content appears. This measures when the largest visible element is on screen, often a big photo or the heading at the top. Good is 2.5 seconds or less, poor is more than 4 seconds.
• INP (Interaction to Next Paint): how quickly the page responds. How long does it take before something happens when you click or tap a button or menu? Good is 200 milliseconds (a fifth of a second) or less, poor is more than 500 milliseconds.
• CLS (Cumulative Layout Shift): how much the page jumps around. You go to tap a button and just then everything shifts down, because a photo or banner has loaded. CLS is a number without a unit. Good is 0.1 or less, poor is more than 0.25.

Anything in between counts as "needs improvement". With real-visitor data, a page counts as good if at least three out of four visits stay within the threshold, measured separately for mobile and desktop. In PageSpeed Insights, you only see INP in the real-visitor data: in the lab test, nobody clicks anything.

The usual causes

Below the score, PageSpeed Insights shows a fairly technical list of things to improve. Here are the usual causes in plain English.

Photos that are too large

A photo from your phone or camera is often thousands of pixels wide and several megabytes in size. On your website it's shown much smaller, but the visitor still downloads the whole file.

How to spot it: PageSpeed lists your images among the things to improve, for example because they're too large or in an older format. In the WordPress media library, you can see the file size of each photo.

Too many or heavy plugins and page builders

A plugin adds a feature to WordPress, such as a form or a photo gallery. Many plugins load their code on every page, even where you don't use them. A page builder, a plugin for dragging pages together, often adds a lot of extra code. It's not just about the number: one heavy plugin can slow things down more than ten light ones.

How to spot it: you have a long list of plugins and no longer know what they all do. Or PageSpeed reports that a lot of code is loaded that isn't used.

Not sure whether WordPress with plugins is right for you? Read our comparison of WordPress vs Wix.

Slow or overcrowded hosting

Hosting is the computer, the server, where your website lives. On a cheap shared plan, you share that server with many other websites. If it's busy, or your plan is too small, the server takes a long time to respond.

How to spot it: PageSpeed reports that the server's initial response takes a long time. The WordPress dashboard feels slow too.

Does better hosting help? Only if the server really is the bottleneck. If the problems are in your photos or plugins, a different plan makes little difference, and more expensive isn't automatically faster. Ask your hosting provider what's going on first.

We don't sell hosting ourselves: you buy it in your own name, from a provider you choose. If you do decide to switch, Hostinger is an option we recommend. We're a Hostinger partner: with our referral link you get 20% off a new plan of 12 months or longer. We haven't compared the speed of hosting providers ourselves, so we don't promise your site will be faster there. Whether a move helps depends on the cause, so measure before and after. To see what hosting costs per year, read our overview of yearly website costs.

No caching

WordPress builds a page from scratch every time someone requests it: the server fetches the content from the database and puts the page together. With caching, the server keeps a ready-made version and sends it straight to the visitor. Not sure whether caching is on? Ask your hosting provider.

Scripts from outside

A chat button, an embedded YouTube video, an Instagram feed, extra fonts, ad trackers: they all load code from another company's server. You have no control over that, and together they add up.

How to spot it: PageSpeed lists code coming from other websites among the things to improve.

Outdated software

WordPress runs on PHP, the programming language on the server. Newer PHP versions are generally faster and still get security updates. WordPress, your theme and your plugins get updates too. If you leave them, you miss out on improvements and run more risk.

How to spot it: WordPress often shows a notice in the dashboard itself if your PHP version is outdated. Under Updates, you can see what still needs updating.

Sliders and large videos at the top of the page

A slider with photos that change every few seconds loads several large photos plus extra code. A background video is even heavier. And that top part of the page is exactly what LCP measures. One good photo with a clear heading loads faster.

What you can do yourself

1. Make a backup first. Or check whether your hosting provider makes a daily backup and how you restore it. If your hosting has a staging environment, a copy of your site, try changes there first.
2. Resize and compress photos before you upload them. Make them roughly as wide as they're shown on your site and save them as WebP, a modern, lightweight format. For photos already on your site, you can use a plugin that compresses images.
3. Clean up your plugins. If you don't use a plugin, deactivate it, check that your site still works properly, and then delete it.
4. Turn on caching. Many hosting providers offer caching in their control panel. If yours doesn't, install one caching plugin, never two at once. Afterwards, test your forms and, for a webshop, the cart and checkout.
5. Check your PHP version. You do this in your hosting control panel. Choose the newest version that your hosting provider and your plugins support. If your site doesn't work properly afterwards, switch back to the old version.
6. Take a critical look at outside elements. Remove what you don't use, such as an old chat button or a feed nobody looks at. For a video, show an image first and only load the video when someone clicks on it.
7. Measure again and compare. Test the same pages as before, a few times, on mobile. Real-visitor data covers the past 28 days, so you'll see an improvement there gradually, within about four weeks.

When it's better to get help

Asking for help makes sense if:

• you've done the steps above and the score stays about the same;
• your site matters for your income, like a webshop, and you don't want to take any risks;
• your theme or page builder is the cause;
• you need to move to another hosting provider;
• updates keep breaking things, or you no longer dare to update.

Then there are roughly two routes.

Your site is basically sound, but hasn't been looked after. Then regular maintenance is often enough. The Complete plan, $59.99 a month, includes a speed check with optimisation. That's also possible if someone else built your WordPress site. We take a look at your site first.

Your site is slow from the ground up. For example because of a heavy theme, a page builder that everything depends on, or a site that has been extended for years without cleaning up. Then you're better off having your website redesigned. Your content moves over and old links keep working.

How do you choose? If the problem is in a few clear things, such as photos, plugins or caching, repairing makes sense. If it's in the foundations of the site, you keep paying for repairs that don't solve the problem. Sometimes rebuilding is cheaper. We'll tell you honestly which route suits your site.

Why speed matters

Many visitors look at your site on their phone. A page that stays blank for a long time or jumps around makes a poor first impression. Someone might go back and pick another business.

And Google? In its explanation of page experience, Google writes that Core Web Vitals are used by its ranking systems. But Google always tries to show the most relevant content, even if the experience on that page isn't great. So a fast site helps, but it won't put you at the top on its own. Relevant content counts for more.

Want us to look at your site? With our maintenance plans, we keep your WordPress site secure and up to date, and the Complete plan includes a speed check with optimisation.