Website Performance Metrics Explained

Why is website speed important

By now, you should need no convincing that website speed is crucial for your online business. That’s because website performance has an impact on your brand reputation, SEO rankings, and conversion rates. Here are the main reasons how and why this happens:

Brand reputation 👍

Let’s be honest, when your website loads slowly, that irritates your visitors and eventually they leave your site. Here are some numbers to back up the argument for you. According to Google, 53% of visits are abandoned, if a website takes more than 3 seconds to load.

The slower your website, the more likely it is for your visitors to leave and be less likely to return ever. If they don’t find what they’re looking for quickly, they won’t interact with your site, as they would consider it inaccessible and unreliable. 

This directly impacts your brand reputation, because visitors would have a bad impression of your site. And we all know that a negative brand reputation is harmful for your online business presence.

SEO rankings 📈

Google and search engines in general aim to provide web users with the best possible user experience. Website speed is an official and important ranking factor in Google’s algorithm, in addition to being a crucial part of your website’s UX. If your website is slow, this will definitely affect your SEO rankings, it will hurt your site visibility among users, and eventually, you’ll start losing traffic to your website.

Conversion rates 🛒

If all these sound scary, wait to find out how a slow website can affect your conversion rates, too! The slower your website loads, the bigger the drop in conversion rates would be. According to a study by Portent, a site that loads in 1 second has a 3x higher conversion rate than a site that loads in 5 seconds. A huge difference in conversions in just a few seconds, right?

How to measure your website performance score

Now that we’re on the same page that website speed is a crucial factor for your successful online presence, let’s explore how to measure your site’s performance score on your side, or what’s usually known as client-side testing. This type of testing helps evaluate if your web application is fast enough by testing what’s happening in the browser.

You can test your website speed with different free online tools. Some of the most popular ones include Pingdom, Google PageSpeed Insights, GTMetrix, webpagetest.org, and others. All you need to do is go to one of these tools, paste your website/webpage URL, and start the test. It will take only a few seconds for the tool to show you the results. 

Now comes the hardest part – the analysis. What does each metric tell you and is there a way to improve it?

What website speed metrics mean and how to improve them

Page load time

Page load time is the time it takes your browser to fully load the requested website. It measures the entire time – from entering a URL or clicking a link until the page finally loads. Ideally, that should happen in less than 2 seconds.

If your site is not hitting this target, your overall page load time can be improved by following the tips for each of the individual metrics below. What is more, if you’re using WordPress, we recommend our free all-in-one SiteGround Optimizer plugin that works on any hosting platform and can save you loads of time and effort in improving the majority of your WordPress website performance metrics.

Time to First Byte (TTFB)

Time to First Byte measures the time it takes for the web browser to receive the first byte of information after sending a request for a resource. A good TTFB result (0.8 seconds or less) means that your browser is responsive. To improve your TTFB, here’s what you can do:

Make sure you run your site on the latest PHP version and have a proper server-level setup. At SiteGround, we have already developed a custom ultrafast PHP setup that has lower memory usage and allows the server to process a bigger number of queries faster. All this cuts the TTFB and makes web pages load 30% faster on average.

Next, check with your hosting provider if they offer full-page caching on your host server. This would store (“memorize”) your web pages on the server and serve them to your users the next time they request them. SiteGround clients take advantage of our in-house developed powerful Caching technology enabled by default, which results in up to 5 times faster sites.

Even if everything is optimized on the server level, as mentioned above, visitors located far from the origin server, may still experience slow TTFB. For this reason and to cut TTFB, start using a content delivery network (CDN). The CDN will use a distributed network of servers that are closer to your users and serve them the content of your website from their closest location. SiteGround has its own in-house built CDN that’s included for free in every hosting plan we offer.

No matter where you’re hosted, though, if your website is using WordPress, you can download and install our free SiteGround Optimizer Plugin. With just a few clicks, you can take advantage of its powerful caching capabilities that can make your site up to 20% faster than comparable plugins.

Time to start render (TTSR)

Time to start render (TTSR) measures the time it takes for the content (i.e. any element from it) to begin displaying on the page after the initial request for the website to load. Lower TTSR keeps the attention of the user because they see the content quickly. A good result for TTSR is less than 750 milliseconds. If your result is not as good, here’s what you can do about it:

First, make sure that you keep your JavaScript, HTML, and CSS files lightweight by minifying them. Minification will remove all unnecessary characters from these files. You can do this yourself manually in the source code or use a tool to help you, in case you’re not so tech-savvy. Again, for WordPress sites, our free SiteGround Optimizer Plugin has an option to enable that with a single click.

Next, optimize and preload the fonts you’re using. To do that, make sure that you’re not using too many fonts (< 4 is best), embed them in the CSS, and optimize them before uploading them on your website. You can do this manually or with the help of our free SiteGround Optimizer Plugin for WordPress where this happens in a click.

Another useful thing you can do is defer JavaScript. By deferring JavaScript, your browser will only process and load JavaScript files after parsing the HTML. This significantly speeds up TTSR, because there’s nothing to block the process of displaying your website on a screen. Again, you can easily do that with the SiteGround Optimizer Plugin for WordPress websites.

Last, but not least, make sure you use the HTTP/2 protocol. HTTP/2 protocol is the latest version of the HTTP protocol and allows browsers to load websites much faster. However, it might be a bit technical to do this yourself, so it’s good to ask your web host about it. If you’re hosted with SiteGround, HTTP/2 protocol is enabled by default on our servers for you.

Time to title

Time to title measures the time it takes for your website’s title to display in the browser tab. This tells your website visitors that your site is loading. It’s an important metric because it shows your users that your site is legitimate and gives them a hint of whether your site will provide them with the content they’re looking for.

If your website is fast enough and you follow the tips we’ve provided in this blog post, that would improve your Time to title as well. To make your website load fast enough, and thus your Time to title, the ultimate solution is to use caching, as this will display the title in the browser tab from the server memory the next time your users try to open your site.

Time to interactive (TTI)

Time to interactive (TTI) is the time it takes for your website to be interactable, i.e. for users to be able to interact with it (scroll, click buttons, etc.). This is a crucial metric, because even if your website loads fully, but is not responding to user interactions, then you’ll lose them again. A good TTI should be less than 3.8 seconds.

To improve your TTI, here are some things to consider. As mentioned above, minification is a powerful way to cut TTI as well. 

Apart from that, make sure to enable compression. Some good compression mechanisms are Brotli (Google’s next-generation compression algorithm) and gzip – they reduce the size of HTML, CSS, and JS files. SiteGround clients enjoy the Brotli compression algorithm out-of-the-box and up to 15-20% speed gains. If you’re hosted elsewhere, ask your hosting provider to find out which compression methods they use.

Last, but not least, eliminate render-blocking resources – eliminate all resources that pause or slow down your website’s displaying on a screen. If you’re doing this on your own, refactor your code or hand-edit your HTML. If you don’t feel like doing it yourself, the SiteGround Optimizer Plugin for WordPress sites provides powerful frontend optimization options which are just a few clicks away.

Connection time

Connection time is the time between a user’s request and an established connection between the user’s browser and your website’s server. Connection time might be slow for your website visitors due to various reasons, such as too much server traffic (e.g. from bots), or users in distant geographic locations from your origin server.

To improve connection time for your visitors, consider hosting your website on a better infrastructure. For example, SiteGround-hosted websites take advantage of the modern Google Cloud platform, which ensures high availability and fast connectivity. 

Using caching and enabling a CDN are other powerful tools for speeding up connection time. SiteGround clients enjoy our in-house developed Caching technology out-of-the-box and take advantage of our free in-house built SiteGround CDN included in all of our hosting plans.

Time to last byte (TTLB)

Time to last byte (TTLB) is when the user’s browser receives the last byte of your website. An average TTLB should be 750 milliseconds per endpoint response. A factor that can influence your TTLB is the quality of your database queries.

To improve TTLB, make sure that your slow database queries are optimized by using a fast MySQL setup. For example, at SiteGround we’ve developed a custom MySQL setup that reduces the number of slow queries between 10 and 20 times and is available out-of-the-box for all our clients.

DNS lookup time

Domain name system (DNS) lookup time measures the amount of time it takes for your DNS provider to translate a domain name into an IP address. If your average DNS lookup speed is more than 120 milliseconds, then you might need to improve it. 

One of the reasons for a slow DNS lookup time could be your DNS provider. Then, you’ll have to switch to a faster DNS provider. Another reason could be the high number of third-party resources on your web pages (that also need to be translated into IP addresses, on top of your own domain name). Reducing the number of third-party resources would improve your DNS lookup speed.

SiteGround customers have the advantage of not having to think about either of the above, because our central anycasted DNS system ensures faster domain resolving and faster website loading. What’s more, WordPress users can enable the DNS prefetch feature in the SiteGround Optimizer Plugin to speed up their websites when loading content from third-party domains.

Performance metrics for user behavior

You can track the performance metrics for user behavior in your Google Analytics. Here are the most important ones:

Bounce rate

Bounce rate refers to the percentage of visitors that leave your website immediately, before taking any action on it. If your bounce rate is high (anything above 46%, according to SemRush), one of the possible reasons could be slow website speed.

Conversion rate

Conversion rate is the proportion of converted users from the total number of visitors on your website. Having a high conversion rate means that your website performs well among your visitors and meets their expectations. In general, a good conversion rate is between 2% and 5%, but you must keep in mind that these numbers might differ for the various industries.

Average time on page

Average time on page measures the average amount of time spent on a single page by all users of a given website. The majority of studies show that the average time a visitor spends on a web page is around 50 seconds, across all industries. If your visitors spend more time on your website, this could be a clear indication for a good user experience.

Error Rate

Error rate refers to the number of requests that return an error code, relative to the total number of requests over a period of time. A high error rate can be caused by issues with your server. The higher the error rate, the less times your site has loaded properly for your visitors, and the less satisfied they would be with it.

Improving user behavior performance metrics

Having a fast and reliable hosting provider can help speed up your website tremendously, which will have a direct positive impact on your conversion rates, average time on page, bounce rates, and error rates. So your choice of a hosting provider is extremely important in any case, but especially when we’re talking about your website speed. If you’re not a SiteGround client already, check our current hosting offers and get a head start on a new website project, or transfer an existing one to improve its performance.

Wrap up

Your website loading speed is a vital part of your successful online business presence. Choosing the right hosting provider in this endeavor could spare you loads of time and effort, as there’s a lot a website hosting provider can do to optimize your website for you, allowing you to focus on growing your online presence.