how pagespeed affect SEO

How PageSpeed Affects SEO? Complete guide.

February 18, 2022

Page speed refers to how long it takes for a web page to load its content. So, wondering how does page speed affect SEO? If pages on your site load slowly, users will be unhappy. If you've ever waited more than a few seconds for a page to load, you know exactly why.

Not only do users get tried of waiting and bounce, but with Google's Core Web Vitals, site speed is confirmed as a direct ranking factor. It's something you can't ignore for search engine optimization, and improving site speed may be the easiest boost to your SEO of anything.

In this blog post we'll discuss all the multiple factors through with slow pages will hurt your Google rankings, and the most common reasons for a slow loading speed. Here's how speed affects SEO.

Table of Contents

PageSpeed Is a Direct Ranking Factor

With Core Web Vitals, Google now claims that page speed is a direct ranking signal. Google offers a speed report inside of Google Webmaster Tools, and reports data collected from the Google Chrome User Experience Report in Google PageSpeed Insights and Google Lighthouse, along with similar lab data.

Why does Google care about page speed? Google realizes that fast loading pages are important to users, and their goal is to show pages that users will like the most. A slow page load time will only be worse on mobile devices, and mobile users now make up over half of all web traffic. If traffic from mobile searches is important to you, then your mobile site speed is also very important.

Slow Page Speed Increases Bounce Rate

We've discussed how Google measures page speed directly, and uses it as a ranking factor, however, there's another factor that is indirectly impacted by slow websites. Bounce rate is another important ranking factor, likely more important than page speed itself. The longer users have to wait for your pages to load, the more of them will hit the back button after getting tired of waiting.

Why does bounce rate matter? It's an easy way for Google to evaluate the quality of results and update rankings based on this. When users click a result in the SERPs, and then immediately click back and pick something different, that gives Google a good clue the user didn't like that result. This could be for a number of reasons, but slowly loading pages are a sure way to higher bounce rates on your website and to hurt rankings in search engines.

Not only does it hurt your rankings, but it hurts your conversion rate too. Fixing your page speed is something you can't afford not to do.

Common Page Speed / SEO Issues

Looking to fix your PageSpeed and boost your Google rankings and get a competitive edge? Here are the biggest reasons for poor page speed. Be sure the check your pages with Google PageSpeed Insights to get an idea of which of these is impacting your load times and speed score the most.

Unoptimized Images

Large image files are usually the biggest reason for a slowly loading website. To properly optimize images, you should use image compression and properly size images based on their rendered dimensions.

Another important image related optimization is known as lazy loading. Lazy loading allow you to only load image files as the user scrolls them into view. Since images are typically the largest kind of files, this can make websites significantly faster.

If your website has a large image above the fold, as many pages do, this is particularly important to optimize as much as possible. This will have a significant impact on metrics like First Contentful Paint and Largest Contentful Paint.

See our full article on optimizing images for more information.

Large Javascript Files

Like images, JavaScript files can impact website's speed significantly. Not only can the files be large, but JavaScript is code that executes in the browser, making it do extra work. This means rendering the page and getting it ready for the user will take longer. To make pages load as fast as possible, you should use a little JavaScript as possible, making sure to remove any unused code.

Slow Server Response Time

Slow server response time can be caused by a number of issues, and will affect all web pages on your website, but it's generally an easy problem to deal with. The first step in the loading process is to start communicating with the web server. You'll notice this issue if you check time to first byte with a tool such as GTMetrix. This also adds the first meaningful paint.

The first step should be making sure you have a caching plugin installed if you're using something like WordPress. There are free plugins like WP Super Cache that make it easy. Without this, your server is doing extra work generating the page for each request. A cache plugin will save the generated pages, and deliver them to users as if they were static HTML pages.

Slow hosting can also contribute here. Don't rush out and rent a dedicated server, but you should use either a good virtual private server (VPS) provider such as DigitalOcean or Linode. If you're using a shared host, your server's performance may not be optimal. You can also consider fast managed WordPress hosting like Kinstra, however a VPS can be just as fast and cheaper.

Even with caching configured, you can still make a big improvement to your server response time. With a content delivery network, or CDN, such as Cloudflare, you can get this number under 100MS. Cloudflare sits between users and your server, and caches you files. They have servers around the globe, so they can get files to your users as fast as possible.

Even if users are close to your server's physical location, a CDN can make a huge difference. Cloudflare's servers require fewer hops than most servers on the Internet, due to their close connections to ISP equipment, meaning traffic to your website may never even leave the ISP's network for the larger Internet.

Cumulative Layout Shift

CLS, or cumulative layout shift refers to how much elements on your page shift around as the page loads. The main contributors to this are images, and then fonts.

For images, this is easy to completely eliminate. You can do it by setting explicit width and height on your images. This allows to the browser to know exactly how much space an image should take on the page before it loads the file. Make sure all images on your page have the correct width and height to prevent them from causing layout shift.

Web fonts can also cause layout shift. This is because although you should enable "font-display: swap" on your web fonts, allowing system fonts to be used a placeholders while they load, this causes layout shifting. A small about of cumulative layout shift isn't a big deal, but you can reduce the shift caused by fonts. See our article on optimizing fonts for page speed for more information on this.

Misconfigured Caching

If tools like PageSpeed Insights report you need to "Leverage Browser Caching," then this means your web server may not be set up to properly set browser cache headers. The exact method to activate browser caching will depend on web server you're using, such as Nginx or Apache.

Browser caching is a fairly simple mechanism. The server simply delivers some headers that instruct the browser long to save a resource. The browser is programmed to look at these headers for each resource it downloads, and not bother with downloading it again until the expiration time has passed.

Long Input Delay

Another issue typically caused by excessive use of JavaScript is long input delay. After reducing JavaScript as much as possible, there's more you can do to reduce your first input delay.

Some JavaScript may be slowing your pages down, but you can't remove it, such as tracking pixels for ad networks. The best way to deal with this is to delay its loading until after the rest of the page has loaded. You can use Google Tag Manager to load your tracking pixels, and set them to load after the page is ready.

Ready To Fix Your Site Speed?

If you're running an online business, or monetizing your website in any way, then you need to make sure your website speed is highly optimized to make the most of your efforts. We've spent years finding all the secrets increasing a page's performance before creating Fastify.

If you're ready to increase your search rankings and your SEO success, then we're here to help. Our courses provide step-by-step video walkthough guides. We also publish free content like this on our blog. Check out all of our resources here if you're ready to see how much speed matters.

Written By 
Mason Wiley
My name is Mason, and I cofounded Fastify after years of experience with SEO and affiliate marketing in a highly competitive industry. I've worked through countless pages of documentation and ran countless experiments to find all the hidden secrets to making screaming fast pages.