How to Improve Website Performance: Everything You Need to Know

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According to a study by Eggplant, 80% of users confirmed that a slow-loading website is more frustrating than a temporarily down website.

An Akamai study revealed a 103% increase in bounce rate for websites where page load time exceeds 2 seconds.

Statista reported that by the end of 2021, there were 2.14 billion online shoppers, but only 2.17% of all online visits converted into sales.

1. Conversion

Conversion rate directly means that visitors perform the actions you want them to. This could be making a purchase, signing up for a newsletter, registering (for a webinar or event), or downloading another guide. According to recent research by Portnet, a page that loads in 1 second has a 3x higher conversion rate than a page that loads in 5 seconds.

While 1 second might seem insignificant on the web, it's an eternity. Taking one of the most significant market players as an example:

A 1-second slowdown in page load could cost Amazon $1.6 billion in sales annually. On the internet, every millisecond counts.

2. Visibility

This is about quickly finding a website on search engine results pages, such as Google. Page speed is one of Google's ranking factors. A well-optimized website provides a good user experience and, consequently, achieves better search results.

Since December 2017, Google's search engine also considers mobile pages. Optimization doesn't just apply to desktop but to responsiveness across all screen types and sizes, especially mobile devices.

3. Usability

Page load time directly impacts building customer loyalty. The better your site performs, the lower the risk of dissatisfied users and a poor customer experience. In a 2016 study, Ericsson found that the stress level of mobile users increased by 33% whenever content loading exceeded 6 seconds. This stress level was comparable to watching a horror movie or taking a math test.

Google's research showed that the bounce rate increased by 90% when page load time went from 1 to 5 seconds. If a page takes up to 10 seconds to load, the chance of a bounce increases to 123%.

There are many challenges, but how do you achieve an optimized and efficient website?

Key Performance Indicators

While speed is instinctive, other performance metrics consist of finer fractions that shape the overall picture of website performance. Website developers (and Google) use several indicators to determine how efficient a given page is.

Largest Contentful Paint (LCP)

The Largest Contentful Paint (LCP) metric is the first Core Web Vital. If the term sounds intimidating, don't worry. It simply indicates the average loading time of the most important content on a webpage.

Both media and text are considered primary content formats. Google uses LCP to evaluate how quickly the first significant piece of information (i.e., LCP) loads. It's about more than just how fast your page loads overall.

If you want to provide your customers with the best possible user experience, a high LCP score is crucial.

Individual websites are evaluated at the page level. To meet Google's user experience standards, a single page's content must load within 2.5 seconds. If the load time exceeds 2.5 seconds, you'll receive a poor LCP score. LCP can vary depending on the type of page. A product image is undoubtedly important information on a product page, but an H1 heading is more crucial for a blog.

If you want to provide your customers with the best possible user experience, a high LCP score is crucial. You increase the likelihood that people will stay on the page and interact with your content if they can access it faster.

First Input Delay (FID)

The second CWV metric is called First Input Delay (FID). It measures the time it takes for a user to initiate an action or command and for that action to be executed on the page. Simply put, it measures your page's interactivity. First inputs include clicking links and buttons, pressing keys, attempting to open a menu, or adding an item to a cart.

According to Google, an FID score of less than 100 milliseconds is ideal. However, if the FID time exceeds 300 ms, website performance will be negatively impacted.

Reducing the impact of third-party code is one approach to improving FID. You can also:

• Use lazy loading for content that isn't critical to display immediately.

• Break up extensive JavaScript operations into smaller tasks.

• Get rid of unused third-party scripts.

You can significantly improve your website's FID score by addressing these issues.

Cumulative Layout Shift (CLS)

Finally, there's CLS (Cumulative Layout Shift). This metric determines how stable your page is during loading.

Have you ever noticed that while a page is loading, images and links seem to shift downwards? This would suggest a high CLS score, giving the impression that page elements are visually unstable.

Users won't make unintended clicks or become frustrated because they're sent to a different page than they intended to see if you optimize your site for this Core Web Vital. Visual stability improves overall performance by enhancing the user experience and reducing confusion.

Bounce Rate

Bounce Rate (BR) is the percentage of visitors who leave a website without taking any action. They don't click a link, fill out a form, or make a purchase. If a page loads slowly, a greater number of visitors will abandon it without interacting. However, bounce rate can be caused by many factors. Therefore, load time may or may not influence it.

Time spent on the website

Time on page or session duration can also indicate slow pages. Again, a poor result might mean that many users didn't get past the initial page load.

Conversion Rate

Conversion Rate (CR) is the number of conversions divided by the total number of visitors. Conversions are closely linked to website performance – satisfied users are more likely to stay on the page and perform the desired action. Similar to bounce rate, many factors can influence the conversion rate, but it's worth checking if performance is one of them.

Error Rate

Error Rate (ER) is the percentage of HTTP requests that return error codes among all HTTP requests within a short period. A high error rate indicates that something is wrong with the network infrastructure, which prevents resources from being delivered, slows down or stops pages from working, and drives visitors away.

Google Pagespeed Insights

Google's free tool conducts a performance test on your site and provides recommendations for improving performance. It's dedicated to both mobile devices and desktops. PageSpeed also indicates CrUX. The Chrome UX Report (known as CrUX) is a public dataset of real user experiences across millions of websites

GTmetrix

GTmetrix is a web performance analysis tool that evaluates page speed and provides actionable recommendations for improvement. It was created by Carbon60, a Canadian hosting company, in 2009. In addition to measuring page load time, GTmetrix also assesses a site's adherence to web performance best practices. These include using a CDN, optimizing images, and minifying CSS and JavaScript.

By following GTmetrix's recommendations, you can improve your site's speed, which can also positively impact your SEO. Furthermore, GTmetrix can be used to monitor a site's performance over time and track the impact of changes you make. This makes it an essential tool for any website owner or web developer who is serious about optimizing their site for SEO and web performance.

WebPageTest

It works well for web experts who are looking for an optimal solution rather than quick wins or a brief, user-friendly summary. A WebPageTest performance audit is very detailed, and preparing it can take longer than reports from other tools. They also recently added a clever feature called "Opportunities & Experiments," which helps identify issues and provides guidance on how to fix them.

Serve Static Assets with an Efficient Caching Policy

A cache is the storage of data in a location where it will be more readily accessible in the future. In browser caching, website data, such as HTML files and images, are temporarily stored on the user's device. When the user returns to a cached website, the browser loads these files from the local cache instead of requesting them from the web server, thereby saving time and bandwidth.

By enabling browser caching, you can store a cached version of your website in the visitor's browser. This ensures faster load times when the user revisits your page.

Browser caching is necessary for static content on a page over a longer period (content that changes frequently should not be cached). How you enable caching depends on the service you use to build and host your website, but every provider should instruct and explain how to set time limits for cached content.

Use CDN

Hosting a website on a single server isn't efficient. When all user requests are sent to the same hardware, the time it takes to process each request increases. Additionally, load times increase the further the user is from the server. Using a CDN can solve this problem.

A CDN (Content Delivery Network) is a set of web servers distributed across various geographical locations that deliver web content to end-users based on their location.

A CDN redirects user requests to the closest server. As a result, content is delivered to the user faster, and the website operates efficiently. This is a very effective way to optimize load times, especially when your site serves many users.

Monitor Page Load Time

Search engine algorithms consider page load time when determining search engine rankings. Page load time matters for SEO, but also for your visitors. A small change can shorten the time and help improve your ranking and user experience. Optimizing page load time is a great way to attract visitors through an excellent online experience and convert them into purchases.

Similar to performance optimization, many factors contribute to page load time, from images to dependencies and CSS files.

Keep an Eye on JavaScript and CSS Files

Having numerous JavaScript and CSS files leads to many HTTP requests when visitors access individual files. All these requests are handled separately by the browser and slow down your site's performance. Reducing the number and size of JavaScript and CSS files will speed up your site.

With HTTP/2, you don't need to group all JavaScript and CSS files into one to reduce the overall number of additional HTTP requests. On the contrary, doing so prevents you from utilizing the Critical Rendering Path technique and forces the browser to download many things it doesn't need.

It's more important to have files that are as small as possible and to reduce unused code (JS and CSS). CSS for above-the-fold content can even be inlined to speed up page loading.

Don't Overdo Third-Party Resources

Third-party tools are integral components of any website, providing useful functionalities suggested by external parties. Unfortunately, the more third-party resources installed, the more resources are required to run them. Consequently, the site slows down, and security issues may arise. It's a good practice to review all installed plugins and remove any unnecessary ones.

How do you manage plugins? Start by running performance tests on your site to identify which plugins are causing slowdowns. Your site's speed depends not only on the number of installed plugins but also on their quality. The most sensible approach is to keep only the essential ones and ensure they are regularly updated.

Consider Dedicated Servers

A dedicated server is a type of hosting where the client has exclusive use of the entire server. Of course, this approach is more costly, but it offers more possibilities for the owner. Shared servers are suitable for websites with low traffic. For online shopping, a dedicated server is the best choice. Heavy traffic and ensuring security should not be shared.

A dedicated server provides the flexibility to compose programs to give your website optimal operational performance. All the bandwidth and processing power on a dedicated server belong exclusively to your website.

Re-evaluate Your Hosting Provider

Or, more precisely, your hosting options. As mentioned above, dedicated servers can be one of the best solutions, but other options also exist:

• Shared hosting: This is the most popular type of hosting worldwide because it's the cheapest way to get your website online quickly and with low fees. Choosing a fast host is crucial for ensuring more satisfactory optimization. With shared hosting, you share the CPU (Central Processing Unit), disk space, and RAM with other websites using that server. Shared hosting is the main reason why this option isn't as fast as VPS or dedicated servers, but it's inexpensive and perfectly suited for websites with lower online traffic.

• Virtual Private Servers (VPS) hosting: Significantly faster than shared hosting. VPS uses multiple servers to distribute content. With VPS, you share a server with other users and own a portion of a virtual server. This ensures that your user configurations don't affect other clients, and vice versa. Other clients don't impact your website. Virtual private servers are best suited for websites with moderate traffic or eCommerce sites with occasional traffic spikes.

• Dedicated servers: A dedicated server is the most expensive and most powerful hosting option. With dedicated servers, all resources belong solely to the owner, and only the owner gets complete control over them. In this scenario, as the server owner, you pay for the server lease as well as for a system administrator responsible for maintenance.

Or Choose Cloud Hosting

An alternative to traditional hosting is renting dedicated cloud resources from AWS, Microsoft Azure, Google, or other public cloud providers. You can even combine both strategies into a hybrid cloud. Cloud infrastructures can also add unlimited on-demand scalability within various packages.

Minify HTML, CSS, and JS Files

To optimize website speed, it's essential to minify HTML, CSS, JS, and other files as suggested by Google Page Speed Insights. Minification is one of the recommendations from Google Page Speed Insights.

Compacting code can save many bytes of data and speed up download and parsing times. The benefits are endless, so there's no reason to wait. With specific development tools or plugins, you can easily remove all extra whitespace, newlines, comments, and so on. Such tools also provide additional support for minifying CSS and JavaScript between style and script tags.

Don't Neglect Image Optimization

As it's likely become clear, many small steps contribute to overall website performance. Restraint is key to success, and optimizing visual assets is an indispensable companion. Image optimization improves page load speed, enhances user experience, and boosts SEO rankings.

Image Compression is Your Ally

It's simple! One of the best ways to reduce image size without sacrificing quality is to compress images using tools like JPEG Optimizer, Kraken, Optimizilla, ImageOptim, and JPEGmini (the pro version also supports video), or something more sophisticated like Cloudinary or WebP Converter. You can also use tools like Squoosh to compare the benefits of image size and quality after optimization. You simply drop the image into the tool and adjust the sliders.

WebP is a modern image format that offers enhanced lossless and lossy compression for images online. Web developers and administrators can use WebP to create smaller, more detailed images that make the web faster. Compared to PNG, lossless WebP images are 26% smaller in size. You can then automate this process using nuxt-image.

Consider lazy load

Lazy loading is the practice of delaying the loading or initialization of resources or objects until they are needed. It's an excellent option to improve web performance and keep visitors engaged. There are many open-source libraries dedicated to implementing lazy loading.

Lazy loading further enhanced by a Content Delivery Network (CDN), which was discussed earlier in this article, is an even better option. By implementing lazy loading while serving resources via a CDN, you ensure that only necessary resources are downloaded, and when a user needs a resource, it is cached and delivered quickly.

Choose Static Files When Possible

Static files are files that do not change while your application is running. Any file can be served as static content as long as it doesn't change in response to user actions or input.

This includes images, JavaScript files, CSS files, and videos. Static content is easier to cache and more efficient. It's unlikely we'll return to fully static websites, but we can leverage the speed and simplicity of static content to improve the modern web.

Secure Your Website's Speed

Performance is an ongoing battle for many professionals. Every online business takes a different approach to its project, based on its unique goals, industry, and audience. So, while the paths to website speed optimization may vary, good website performance is the ultimate goal for all sites, regardless of service, content, or approach.

Therefore, we recommend adopting a simple yet effective approach to website speed optimization:

1. Review and evaluate your website's critical success factors, considering conversion, visibility, and usability.

2. Always strive to understand user behavior accurately. What devices are they using? What type of connections do they use, and which countries do they come from? This will help you optimize your website for your target audience.

3. Test your current website speed and prioritize the pages and features that require the most attention concerning the three factors mentioned above.

4. Check or consult whether any of these can be automated. Consider the impact of your old tech stack on the compositional capabilities available in the market.

5. Start optimizing with the ultimate solution and focus on the pages that contribute most to conversion success.

SpeedCurve

It allows you to assess website performance and provides detailed feedback, including page size and page load time. SpeedCurve dashboards offer several different viewpoints and choices.

Pingdom

Mentioned earlier in this article, Pingdom is also a top choice among website monitoring tools. It offers both real user monitoring and synthetic monitoring. It's valued for its reliability and timely alerts issued when a site goes down or performs below standard.

Uptrends

It's a popular monitoring tool that provides proactive and reactive solutions for website monitoring. It offers highly intuitive and visually engaging reports and plans tailored to the needs of both smaller and larger market players.