Website speed and performance are massive parts of SEO and user experience. A site with poor speed is more likely to negatively impact user experience, but it is also more likely to rank lower in a Search Engine Results Page (SERP). Google considers Core Web Vitals (CWVs) when positioning websites in a results page, meaning that a website which runs slower is more likely to appear below a faster one. So, how do you complete a site speed audit and improve performance?
Website speed can be audited using various (free) tools available on different websites such as Google PageSpeed Insights, GTmetrix, ShortPixel, and DotCom-Tools. These tools will help to identify problem areas of your website, guiding you to make the improvements required to boost performance and deliver stronger rankings.
Read on for more information with a step-by-step explanation of how to audit site speed, along with information about why site speed should be considered for SEO and how we can improve any issues we find.
“At Wildcat Digital, our approach to improving our clients’ website performance involves a comprehensive approach that analyses data from a range of sources to pinpoint problems and implement precise, widespread improvements rather than chasing single slow URLs.” – Paul Pennington, SEO Account Director
Jump To:
- How Do I Conduct a Site Speed Audit?
- What Are the Causes of a Slow Website Speed?
- How Do You Improve Website Speed?
- How Does Website Speed Affect SEO & Rankings?
How Do I Conduct a Site Speed Audit?
To make improvements to a website’s speed, we must first understand where the website is failing. Luckily, there are various tools we can use, free of charge, that run website performance audits to give us a good idea of where improvements can be made. We’ll go through each tool, explain what the tools hope to achieve, and any potential opportunities they identify.
Evaluate Core Web Vitals Performance – High Priority
PageSpeed Insights is a free tool from Google that gives us a look at how they rank your site speed and performance on both Mobile devices and Desktop. You can also access this data using Google Lighthouse. Core Web Vitals are a key ranking factor for Google and cover measurements of:
- Largest Contentful Paint (LCP) – This measures how long it takes for the largest piece of visible content to load on a screen, such as the hero image or big heading.
- Interaction to Next Paint (INP) – Tracks how fast the page reacts once a user clicks, types or taps on the page during their visit.
- Cumulative Layout Shift (CLS) – Records if on-page elements unexpectedly jump or move while the page is loading.
Below are examples of a PageSpeed Insights test.
Mobile Test:
Desktop Test:
The majority of websites have a worse mobile score than desktop score. It’s advised to have a score of at least 90 or higher if possible, though a score in the 50+ range is considered average and functional.
As Google is a mobile-first crawler, it is important to take careful consideration of your website’s mobile score in PageSpeed Insights, as this will give an indication of how Google will rank your site.
Below are the data analyses of mobile and desktop. These focus on the metric times that do or do not need improvement. One of the main focuses we’re looking at is LCP, which should not be any more than 2.5 seconds. Ideally, we’d like to make this less than 2 seconds. While CLS isn’t to do with site speed, this is another SEO factor within Core Web Vitals which needs to be 0.1 or less.
Mobile:
Desktop:
Google will then give advice regarding “Opportunities”. Shown within this area are the potential areas that can be fixed to improve the overall PageSpeed Insights score for desktop and/or mobile.
It’s clear in this example that mobile has a few areas that need help, including:
- Reduce unused JavaScript
- Reduce initial server response time
- Eliminate render-blocking resources.
Mobile:
Desktop:
Further Core Web Vitals Review – High Priority
Within Google Search Console, you have access to a Core Web Vitals report. Using this tool will help you identify site-wide trends relating to URLs on your website that are experiencing poor performance, allowing you to isolate the root cause.
Review Global Site Speed – Medium Priority
DotCom Tools has a free speed test tool that’s used to test the page loading speed that users will see from different areas of the world. This tool tests the first and second visits because the second visit is usually faster due to a page or browser cache. We want around 2.0 seconds load time or less. Anything over 3.0 seconds needs to be fixed.
If your website is for a business that only offers services located in a specific country or state, then the time to load the site within that area is the most significant.
Gain Further Site Speed Insights – Medium Priority
GTmetrix is another free tool that helps analyse website speed performance.
GTmetrix offers similar advice to Google PageSpeed insights but also gives more information on other potential improvements such as using a Content Delivery Network (CDN) to serve pages in different geographic locations. CDNs cache pages on their servers in certain countries so that it loads faster the next time someone in that area or location goes on the website.
Evaluate Image Compression – Medium Priority
ShortPixel is a free tool used to see if you need to compress any images on your website. While it isn’t always fully accurate in terms of potential percentages of image compression, the website gives you a general idea of whether images could be compressed or served as next-gen files to improve overall loading times.
What Are the Causes of a Slow Website Speed?
So, now you know how to audit your site speed, but what is actually causing the issues that the audit has identified? Some of the main culprits that are slowing your website down and costing you visitors, rankings, and enquiries are included below.
Images
Typically, evaluating your website’s image compression will identify some immediate issues. For example, hero images may be delivered at a file size of 5MB when it should really be around 200KB. Serving such large file sizes will slow down processing time and burn bandwidth.
JavaScript
Some single-page applications use hundreds of KBs of JavaScript before reaching your website’s users. This can cause a significant delay in a page becoming interactive, as the browser must process all of this code.
Fonts
Best practice dictates that static assets such as fonts have a cache expiry of at least 30 days; however, if this has not been set, assets may expire after a very short amount of time. This means that fonts, images, stylesheets, and JavaScript files will be redownloaded every time, so returning users see no improvement in site speed.
Third-Party Scripts
Code from outside sources such as Google Analytics, chat boxes, and social buttons all compete for both bandwidth and processing power. Each of these third-party scripts can load even more scripts, which ultimately results in a substantial page load time.
Learn more about identifying technical issues with your website by reading our blog: What is a Technical SEO Audit & Why is it Important?
How Do You Improve Website Speed?
When learning how to improve website speed, there are a few initial considerations. The first thing to consider is the Content Management System (CMS).
If you’re on a CMS that limits access to certain areas of the administration area, such as the website code, it may be harder to improve website speed than if you had access.
Another thing to consider here is that, even if you do have access to these areas, you may have a hard time understanding or putting into practice the potential improvements.
This is where you may need to hire a web developer, SEO expert, or site speed specialist.
Content Delivery Network
A Content Delivery Network (CDN) is a network of servers placed in many geographic locations throughout the world. This decreases the load times of the website within these locations by caching pages on the servers. If you’re looking for a reputable CDN, Cloudflare offers a free CDN service along with other security and performance services.
Reduce or Minify Code
Excess or unused code within websites is common. It’s therefore a good idea to reduce, remove, or minify code that would otherwise cause longer load times.
Compress Images
When an image is first saved, it can usually be compressed to reduce irrelevant image data so it’s a significantly smaller size (in terms of load), but the image quality isn’t affected so much that it ruins user experience.
With the creation of new-gen image files such as WebP, images can now be saved as this file type and served on websites to reduce loading times even more.
Plugins
If your website is built on WordPress, you have many options to improve website speed. Deactivating and deleting excess plugins has been shown to improve site speed and performance dramatically.
However, there are additional plugins that can help improve site speed. A backup from the host (not from a plugin) should always be downloaded before installing any plugin. These plugins include:
- WPRocket – WPRocket is a premium plugin that offers a 14-day refund clause if the plugin either doesn’t work or causes issues. This plugin helps to reduce render-blocking resources, minify JavaScript/HTML/CSS, among many other benefits.
- Asset Clean Up – this free plugin works alongside WPRocket to boost site speed.
- Imagify or ShortPixel – both of these plugins compress images; however, if you have a large number of images that need compression, you will have to pay a small amount of money. Both plugins offer the option to serve images in WebP (new-gen image file), which speeds up the image loading times even more.
- W3 Total Cache – If you can’t afford the premium prices for WPRocket, try W3 Total Cache. It’s the best free cache plugin WordPress has to offer and is similar to WPRocket, but less effective.
Read more on technical SEO by reading our article: Technical SEO & Site Health: How to Build a Search-Friendly Website
How Does Website Speed Affect SEO & Rankings?
Since 2010, Google has been using site speed as one of their ranking factors and has said on regular occasions that a faster site will help you rank better. However, rather than overall speed being a direct ranking factor, Google has included certain areas of site speed and other user experience metrics within its Core Web Vitals.
Website speed can affect user interactions on a website. While this is bad for conversions (i.e. sales or enquiries), this is worse for SEO. If a page is taking a large amount of time to load, a user will likely become frustrated, impatient, and/or bored, then click off the page back to Google to find a faster, more efficient website.
This shows Google that the slower website isn’t helpful to users, as the bounce rate from the website towards another website is high. This will then rank other, quicker websites higher, as this shows Google those websites have helped users more effectively, as there are more user interactions.
Learn more by reading our detailed blog: How Important Is Site Speed for SEO?
Technical SEO Services at Wildcat Digital
If site speed performance, tools and fixes are still leaving you a little confused or unsure of what you need to do, our expert SEO team at Wildcat Digital can help.
Site speed is one of the first technical SEO tasks that we complete as part of your campaign to help get things moving in the right direction.
Get in touch with us today to learn more about our SEO services.
Andy Blanchard
Senior SEO Executive
