WordPress site speed

Top 5 items that can slow down a WordPress website

Do you want to speed up your WordPress site? I am sure your answer is yes, why wouldn’t be so here we go through the top 5 items that can slow down a WordPress website.

Fast loading pages are a necessity and improve your overall visitor experience, increasing your stickiness as a site, and help with your WordPress SEO. In this article, we will look at some of the most useful WordPress speed optimisation tips.

We are not going to go into the specific plugin in details but categorise the main problem areas with tips to take action.

Why speed is important for a WordPress site?

The time it takes for a page to load is an important part of any website visitors experience. Your WordPress design is a critical balance between wacky features and speed, with all too often the website owner wants wacky features and the visitor wanting speed.

The average user has no patience for a poor page load and they will abandon your website and pick the next listing in the search results. There are many studies into speed vs abandonment, but in our opinion, 2 seconds is the ultimate maximum and the more you can shave off below this the better retention is.

Another key factor is that in the last two years we now expect a mobile experience whilst out and about to be comparable with a desktop experience at home or work.

Understanding your WordPress website speed

You have to take a scientific approach to understand your current WordPress website speed. If you just hit some pages on your desktop computer or your own mobile then all too often you get a false sense of optimism.

Your computer understands you often visit your own site and so will make efforts hidden to you to speed up. This will be true in any frequent visitor to your site but we would guess that it is the first time visitor you want to impress and convert into some form of sale.

Before you do any checking you need to understand your visitor profile, this includes the location they come from and the device and browser they use. For example, if you have 90% traffic from one country then that is a simpler exercise than an even distribution across Europe and America.

When you know your audience we recommend running through our two favourite tools:

This will give you the key top items to solve but once you get into the finer improvements then we would suggest you start to use something like the Chrome/Firefox Browser Developer Tools.

What are the top 5 items that slowdown a WordPress website?

So you have a speed test report from the above step and I am sure will have a list of recommendations for improvement. However, I am sure most of the recommendations are explained in technical jargon that the average business WordPress user will struggle with and also don’t want to be exposed to.

Having an awareness of what slows down your website is a key element to improving performance and having a website that delivers on its promises.

Out top 5 causes for a badly performing WordPress website are:

  • Website Hosting – Your web hosting server is doing all the work behind the scenes and a short cut or cost-saving here will cost 10x in speed later on.
  • WordPress Caching – A site that is not serving cached pages, will all too often overload your hosting server, causing your website to be slow.
  • Page Size – Modern websites use a lot of high-quality images and any large images that aren’t optimized for the web can cause your users to abandon before the page loads.
  • Poor Plugins – Not all plugins are the same, if you’re using a poorly coded or maintained plugin, then it can significantly slow down your website and cause a big security risk.
  • External resources – External scripts such as ads, analytics, maps, font loaders, etc need to be managed as they can also have a large impact on your website performance.

We will explore each of these top 5 items that can slow down your WordPress website.

Website Hosting

Web hosting is one of the key components of a successful website. There are various different types of WordPress hosting options available such as Free, Shared, Virtual Private Server (VPS), Dedicated, and specialist managed WordPress hosting.

Speed, security, and reliability are all important factors that you need to consider when choosing your WordPress hosting. However, you need to treat this as a partnership and consider what you need today and what you will need to become in 6, 12, 18 months time. Evaluating a hosting partner is making sure they can adapt and scale as your business website does.

Hosting can cost from nothing to £100s a month and to some extent, you get what you pay for, the big question is what do you need today.

We would generally recommend a Free or Shared Hosting option is only good for a low volume simple information site and if you want complex functionality, rich with images you should be thinking of a VPS or specialist WordPress hosting.

WordPress Caching

WordPress is a dynamic site in that every time a page is requested it is generated and depending on the number of plugins you have this can be a very costly exercise. You have two tools to help in this, the first is a server cache and the second is a Content Delivery Network (CDN).

A cache plugin will instead of making a page on every request, saves a copy on the first load, and then on subsequent requests will serve the cached page to the visitor. The length of time you can use the cached version depends on the site content, for example if you have something like the weather then you will have more restrictions than a static information page. In either case, you can gain benefit in not only faster pages to your users but also make more efficient use of your web hosting resources, helping you with the overall bill.

The other element is a CDN, these take static elements of your WordPress website, for example, images and script files and rather than serving them from the server they are served from a CDN which is a worldwide network of servers. This has benefits on reducing requests on your own server but also because a CDN is worldwide the files are served faster as they can be closer to the website visitor. One of the most popular CDNs is Cloudflare which for most business website the free option should be sufficient.

Page Size

A lot of factors influence the page size but the first one you should do is to optimise your image sizes. Images are becoming more important in attracting visitors to your website and because of this, images can be one of the biggest influences in page speed and a number of techniques can be used to speed them up. This optimisation falls down into two stages – before you upload them to your WordPress website and then once they are on your website.

Modern cameras create huge photos and these should be optimised before uploading using editing software on your computer. Two simple steps, the first is to re-size the photo as default sizes will be at least 2x the size needed. The second step is to then compress the image and this can decrease the size by up to 5x.

Once uploaded some cache plugins provide tools to further optimise the size including adapting to web image formats, to server from a CDN and to do something called lazy-loading. Lazy-loading is where rather than wait for the file to be transferred the page will show a holding space that is then populated allowing the visitor to start reading text and interacting whilst the image is still be transferred. lazy-loading also only transfers images that are in the current viewing space and as you scroll sown will load images as they come into view.

Our advice is clearly to sort out your images before even thinking of more advanced page size optimisations.

Poor Plugins

WordPress has a whole ecosystem of plugins that just about solve any problem you are likely to meet. The problem is the quality of these vary significantly and some are poorly maintained which can, in turn, cause performance and security issues with your own website.

Thus, we recommend that you thoroughly investigate every plugin before installing and there a few key items you should be checking:

  • Last updated date – this indicates how current it is and something not been touched for over 6 months should be handled with caution
  • Compatible with your version indicator – this just tells you the developer has tested and verified with your current version of WordPress
  • The number of installations – if you are comparing plugins then one with thousands or millions of installs should be considered before one with 100’s.
  • Reviews – take this one with a pinch of salt as like in all reviews you only get the extremes and so it becomes a proportion of reviews against installs indicates if worth considering as all those who have not left a review tend to be in the most part happy
  • Then do some general google searches around “What WordPress plugin does XXXX?”

Then the most critical element is ALWAYS keeping all your plugins and base WordPress version up to date. Most security issues come from old versions of plugins and badly maintained plugins.

External Resources

The last of our top WordPress speed points are external resources. By this, we mean items used on your website that you take from other places on the internet.

Sometimes you can’t help as when you install a plugin it uses a font loaded from Google or a script loaded from the plugin developers website. The main consideration here is to make sure that these resources are loaded in a way that they don’t slow down the overall page, this is often referred to as asynchronous or deferred loading and a lot of the standard WordPress cache plugins also provide help to configure this.


We hope you found our introduction to the top 5 items that slowdown a WordPress website useful. By focusing on these we are sure you will gain good WordPress speed improvement and once you have cracked these then you can start on the more advanced options that give good benefits but not such a big step change as those listed above.

If you would like any help then please get in touch and we would be happy to chat about your website and possible options to improve.