12 Reasons Your Website Is Slow And How To Improve It

If you want to build a successful online business in 2021, website speed is critical. Fast-loading websites improve SEO, enhance user experience, lower bounce rates, and most importantly — boost conversion rates.

Recent research shows that the average desktop site takes 10.3 seconds to fully load, while mobile sites take even longer — around 27.3 seconds. That’s a problem.

Site speed directly affects your website’s success. It influences how visible your site is in search engines and how likely users are to convert. While it’s clear that optimising performance matters, figuring out where to start can be challenging.

The good news? You can easily run speed tests to see how your site compares to others. If it’s underperforming, there are common fixes — from using quality WordPress plugins to upgrading your web hosting.

In this article, we’ll explain why site speed matters, and then cover 12 common issues that slow down your site — plus how to fix each one. Let’s dive in!

• Website speed is crucial for online business success — it boosts SEO, improves user experience, lowers bounce rates, and increases conversions.
• Average load times are too long: desktop sites take 10.3 seconds, mobile sites 27.3 seconds — far from ideal.
• Slow speed harms SEO rankings and user engagement. Even small delays can drastically increase bounce rates and reduce conversions.
• Common causes of slow websites include: no CDN, render-blocking JavaScript, database overhead, lack of caching, unoptimized CSS, large media files, bulky code, and plugin issues.
• Easy fixes can have big impacts: enabling caching, compressing images, minifying code, and upgrading hosting are quick wins.
• User ISP issues can also affect load times — testing connections can help diagnose these problems.
• Regular speed testing with tools like Google PageSpeed Insights, Pingdom, and GTmetrix helps identify bottlenecks and measure improvements.

Table of Contents

1. Key Takeaways
2. How Website Speed Impacts SEO, UX, and Conversions
3. 12 Reasons Your Website Is Slow (And How to Fix Them)
   • Not Using a Content Delivery Network (CDN)
   • Render-Blocking JavaScript Delays
   • Excessive Database Overhead
   • OPcache Not Enabled
   • Unoptimized CSS
   • Caching Issues
   • Large Media Files
   • Complex or Bulky Code
   • Poorly Written Scripts
   • Plugin-Related Slowdowns
   • Missing Files Causing Errors
   • User Internet Service Provider Problems
4. What Causes Slow Performance on Some Websites
5. FAQ

Today’s users expect websites to load fast. When a page takes too long, it hurts the user experience (UX) — and that affects your conversion rate.

Slow-loading pages often lead to higher bounce and abandonment rates. In fact, studies show that just two extra seconds of loading time can increase bounce rates by up to 103%. Even a small delay — as little as 100 milliseconds — can lower conversions by 7%.

Every fraction of a second counts. That’s why improving your website speed is crucial. A fast site keeps users engaged and increases the chance they’ll take action.

Website speed also affects visibility. Google now considers site speed a ranking factor for both desktop and mobile searches. If your site is slow, it may drop in search engine rankings, leading to fewer visitors and missed opportunities.

You can’t afford to overlook site performance. It influences how users experience your brand and whether they find your site at all.

If you’re unsure where you stand, start by testing your current speed and rankings. Tools like Google PageSpeed Insights can help you identify issues and recommend improvements.

Load time testing shows how long users wait before they can take action. Once you know your baseline, you can take steps to speed things up and improve results.

Once you understand how your site is currently performing, you can start making improvements. Focus on the key factors that affect speed. Below are 12 common issues that slow websites down — along with simple ways to fix them.

An Internet Content Delivery Network (CDN) is a collection of servers that are deliberately placed across a geographic region. You may use them to keep copies of your website, allowing users who are situated far away from your main server to see its pages more rapidly than they would otherwise.

There are a variety of CDN solutions available for your WordPress website. Cloudflare, as well as the Jetpack CDN for pictures and videos, are two of the most popular content delivery networks. 

Additionally, if your website makes use of jQuery, you may have it loaded via a content delivery network (CDN) rather than your web server. 

Because jQuery requires much fewer lines of code than JavaScript to achieve the same results, it may be very helpful for improving the performance of your website. Google CDN and Microsoft CDN are the two most common jQuery content delivery networks.

JavaScript is the code that enables users to connect with and interact with your website via the use of scripting languages. It is written in Java. Your website would be very uninteresting if it didn’t have it. JavaScript, on the other hand, may cause your sites to take longer to load in visitors’ browsers if they are not optimised.

When a browser attempts to show a website, it must first pause and completely load any JavaScript files that it finds on the page. Because of this, “render-blocking JavaScript,” also known as JavaScript that stops the website from loading rapidly, is generated.

There are three options for dealing with JavaScript that causes rendering to be halted:

Remove the need for external JavaScript files and replace them with inline JavaScript.

Asynchronous loading is used so that JavaScript may be loaded independently of the rest of the page.

Another primary issue with Display Blocking JavaScript is that it causes the browser to take longer to render the essential information that the user has come to view — particularly, stuff that is visible above the fold.

As a result, one method of resolving the problem is to delay the JS loading so that it occurs after the essential portions of your page have completed loading. This may aid in preventing resource contention and improving performance at the same time.

There may be instances when your theme or plugins contain external JavaScript that causes the browser to request and download the JavaScript from another location. As you might guess, this increases the time it takes for your website to load.

Now, if the external scripts are tiny, you may include them straight in your HTML page without modifying anything. This eliminates the delay associated with network requests.

Excessive objects in your site’s database are referred to as “overhead.” Things like logs, transients, and other entries from plugins or themes are examples of stuff that may collect over time and need to be cleaned out.

When there is too much of this “overhead,” database queries may take longer to complete than they should. If your web server is waiting for a response from your database, your web server may time out altogether.

This may be avoided by optimising your database and eliminating unnecessary overhead. You can usually access the database administration software phpMyAdmin via your web hosting account, which is standard practice. 

WordPress Command Line Interface (CLI) may be used to optimise tables if you are unable to do it via the phpMyAdmin interface (WP-CLI).

OPcache is a caching engine that comes pre-installed with the PHP programming language. It is possible that having OPcache enabled on your site will help speed up the loading of the PHP script and, as a result, the loading of your pages if you are using PHP on your site.

By default, OPcache is enabled on all of our Shared WordPress and DreamPress hosting services. In-depth your site is hosted by one of our other plans or by another web host, you will almost likely need to manually activate it.

Because CSS — the code responsible for creating your site’s pages — isn’t optimised, it may cause your site’s pages to load slowly, similar to how JavaScript causes pages to load slowly. There are a few methods you may put in place to get your CSS in better condition:

• Combining several external CSS files into a single or a few files is recommended if you have a lot of them.
• Remove any external CSS and replace it with inline CSS.
• When specifying when specific CSS files should be loaded, use the term “media types.”

Inline CSS is similar to inline JavaScript in that it is only suitable for short sections of code.

If you have many big CSS files, you should avoid attempting to include them all on your HTML page. The use of media types and the merging of your external CSS files (if you have more than one) should have a more significant impact on the speed of your website.

Caching is the process through which browsers save static versions of the files on your website. When visitors visit your site, their browsers will be able to show the previously cached material without having to refresh it.

WP Super Cache is one of many caching solutions accessible to WordPress users, and it is recommended that you install one of these caching plugins.

Media assets, such as pictures and movies, are notoriously big in file size. Making them smaller by compressing them may assist to reduce their size and, as a result, improve the loading speeds of your web pages.

TinyJPG is a free internet application for compressing pictures that you may use anywhere. There are also many plugins available for WordPress that may be used to compress media assets, including Smush Image Compression and Optimization.

Video compression is more difficult than it seems, therefore it is generally preferable to host videos outside on YouTube or another platform rather than inside your website. You will then be able to simply embed your videos into websites or blog entries.

The greater the amount of code that must be loaded by your user’s web browser, the longer it will take for your website to become accessible. 

If your code is excessively “bulky,” or if it includes superfluous characters and line breaks, your website may load more slowly than it should. As a result, you may “minimise” that code by eliminating the parts that aren’t required.

Two common plugins may be used to accomplish this job. Autoptimize minifies code, as well as inlining CSS and optimising JavaScript files, among other things. It also works nicely in conjunction with WP Super Cache.

Poorly coded JavaScript may sometimes create incompatibility problems with other sections of your website, resulting in slower page loading speeds as a consequence. 

Pingdom, Web Page Test, and GTmetrix are all tools that can be used to speed up your website’s loading time and discover scripts that are taking an excessive amount of time to load on your website.

You may then look at these files in-depth to see if there is anything you can do to enhance them. It may also be beneficial to temporarily disable possibly troublesome scripts to observe how your performance ratings change as a result of not having them enabled.

Having an excessive number of plugins, or even a few extremely large ones, may slow down your website’s speed and cause it to crash. It’s a good idea to always fully uninstall any plugins that aren’t currently in use to reduce the likelihood of this happening.

Some plugins, in addition to interfering with the caching of your website’s pages, may also cause problems. If you’re using the Proxy Cache Purge plugin, you can find out which plugins are causing the issue by going to Proxy Cache > Check Caching and looking for the plugins that are causing it.

WordPress doesn’t have all of the files it needs to run properly. Adding more queries to try to locate the files will result in slower loading times for users. If the files aren’t discovered, you’ll get a 404 error message.

There is a wide range of factors contributing to this problem, so instead of attempting to isolate the cause of the issue, you should restore your website from a recent backup instead. This will restore the files from your backup and replace the missing ones.

Sometimes, slow website performance isn’t your fault — it could be your user’s Internet Service Provider (ISP). Network congestion, bandwidth limits, data filtering, or content screening can all cause delays.

To check if the connection is the issue, you can run a traceroute between your computer and the website. This will help you determine whether the problem is related to a specific ISP or affects the entire site.

The speed and responsiveness of your website play a major role in its success. That’s why any opportunity to improve performance is worth the effort. Identifying what’s slowing down your site can boost both SEO and user experience — leading to better visibility and more conversions.

This article covered twelve common reasons for slow website performance. While every fix is helpful, you can start by focusing on key areas like enabling caching or compressing media files. These changes can quickly resolve the most pressing issues.

When you need a hand in analysing what may seem to be slowing down your website, our on-page SEO helps. Call us here at TopRankings and will measure website speed from a usability standpoint, gauging it against industry competitors to help you improve your site’s overall SEO performance and level the playing field.

Why is website speed so important for SEO?

Google uses site speed as a ranking factor. Faster sites provide a better user experience, reducing bounce rates and increasing the chances users will stay and convert, improving your SEO performance.

What tools can I use to test my website speed?

Popular tools include Google PageSpeed Insights, GTmetrix, Pingdom, and WebPageTest. These tools analyze your site’s load times and provide recommendations for improvement.

Q3: How does a Content Delivery Network (CDN) improve website speed?

A CDN stores cached copies of your site on servers worldwide. When users access your site, the CDN delivers content from the nearest server, reducing load times and speeding up your site.

Can large images really slow down my site?

Yes. Large, uncompressed images increase page size and load times significantly. Compressing images or hosting videos externally can drastically improve site speed.

How do plugins affect website performance?

Excessive or poorly coded plugins can slow down your site and cause conflicts. Removing unused plugins and using lightweight, well-coded plugins can improve speed.