Top 10 Reasons Your Site Loads Slowly (And How to Fix Them)

1. Unoptimized Images

A large volume of unoptimized images is usually the most common reason behind website slowness. High-resolution images can consume lots of bandwidth while loading. Uploading large images and then scaling them down in the browser unnecessarily increases the size of your web page, which makes it load slowly. This is true regardless of what CMS or website builder you use.

The image format is another important factor to consider.

Pick the format that suits the content: JPEG for photos, PNG or SVG for flat graphics and logos, and WebP or AVIF where your CMS supports them, as they are usually smaller still.

Takeaways:

• Check the file size of your images, anything above 1MB is really unacceptable.
• Use JPEG for photos, PNG or SVG for graphics, and WebP or AVIF where your CMS supports them.
• Use waterfall tests to easily scan image sizes and take corrective action.

2. JavaScript Issues

The availability of JavaScript/jQuery plugins has made it really convenient to add dynamic content to websites. However, if implemented incorrectly, JavaScript can cripple your website's page load speed.

It takes time for jQuery & JavaScript to be loaded, interpreted and executed. So if you are using multiple API calls to render JavaScript/jQuery data, it can result in significant delay while loading the web pages.

Takeaways:

• Load scripts asynchronously, and consolidate tools behind a single tag manager.
• Consider using something like Segment or Google Tag Manager. A single script for all your tools!

3. Heavy Video and Animation Embeds

Autoplaying background videos, embedded players and heavy animation libraries are a common cause of slow pages. They are large, they often pull in third-party scripts, and they compete for bandwidth with the content your visitors came for.

Load video players only when a visitor presses play, show a lightweight poster image until then, and prefer CSS animations to large script libraries. If you want to make your website faster, this is often one of the quickest wins.

Takeaways:

• Video embeds and animation libraries are heavy.
• Load video players on click, not on page load.
• Prefer CSS animations to large JavaScript libraries.

4. Excessive HTTP Requests

Having loads of JavaScript, CSS, and image files can lead to too many HTTP requests. When a user visits your web page, the browser requests each of these files, and the ones that block rendering delay the page. HTTP/2 and HTTP/3 carry many requests over a single connection, so many small files cost far less than they used to; total bytes and render-blocking files are what matter most today.

Takeaways:

• Make sure your server supports HTTP/2 or HTTP/3.
• Defer or remove render-blocking CSS and JavaScript where possible.
• Minify your CSS and JavaScript files to reduce the bytes visitors have to download.

5. Not Making Use of Caching Techniques

Enable browser (HTTP) caching for static files and server-side page caching for dynamic pages; our PHP caching article covers OPcache, object caches and page caches.

6. Unclean Code

Another common culprit for website slowness is unclean coding. When you make your website, excessive white spaces, inline stylings, empty new lines and unnecessary comments can make the website stylesheet grow larger in size.

By removing these unnecessary elements, you can compress the code, reduce the file size and improve the overall page load time and if you're tracking rankings you'll probably see a boost in your SEO performance too. In technical terms, this process is known as minifying. If you are not comfortable with coding, there are several online tools that can be used to clean and minify your stylesheet files. Alternatively, a developer can do it for you as part of your build process.

Takeaways:

• Avoid inline CSS.
• Try not to create multiple CSS stylesheets when you can use a single one.
• Minify!

7. Not Using Compression (gzip or Brotli)

By enabling gzip compression, you instruct the server to compress each text response (HTML, CSS, JavaScript, JSON, SVG) before it is sent to the browser. Brotli compresses smaller still and every modern browser supports it. Images such as JPEG, PNG and WebP are already compressed and gain nothing from it.

Takeaways:

• gzip or Brotli compression is an easy performance win.
• It compresses each text response (HTML, CSS, JavaScript) before it is sent to the browser.

8. Too Many Ads

The most obvious impact of overloading your website with advertisements is the addition of HTTP requests, which would need additional processing time.

Rich media ads, like pop unders, interstitials and auto downloads, may create hundreds of HTTP requests making your website unresponsive.

Load ads with a short delay, after the main content has rendered.

9. Not Using a CDN Service

A CDN serves static files from a node near the visitor. It helps most when your audience is spread across regions; for a single-country audience on a well-placed server it changes little.

10. Your Hosting Platform

If you have worked through all of the causes above and your website still responds slowly, look at the platform underneath it. Choose a hosting provider that includes performance tuning in the service.

Managed hosting should include this.

At EuroVPS we build the web stack around your application, whether it runs WordPress, Magento, PrestaShop or Drupal.

Conclusion

At EuroVPS, our support team can review your web server and PHP configuration with you and help you find what is slowing your site down.