9 Essential Strategies for Web Performance Optimization

First impressions are everything. When it comes to your website, lightning-fast page speed and responsive design help you put your best foot forward. 

It can also increase your sales. Improving mobile page speed by just a half second can lead to an increase in conversion rate, while also decreasing your bounce rate. On the other hand, 54% of people say that as the load time for an ecommerce site increases, their frustration does too.

This shows the speed with which a website loads makes an important impression on the user. Website performance optimization aims to improve a site’s technical performance, which can speed it up and, in turn, help you retain users. Here’s how to optimize your website’s performance for better business results.

What is web performance optimization? 

Web performance optimization is the process of improving the speed and responsiveness of a website. It involves strategies to minimize page load times, reduce web server response times, improve resource delivery, and enhance a website’s functionality on both desktop and mobile. 

You can optimize a website through several back-end measures, including limiting image sizes, refining the site’s code, and ensuring your web server meets your business needs. 

An optimized webpage loads and becomes interactive quickly. Text boxes and interactive elements operate correctly, and animations and videos play smoothly. If you have a heavy webpage that is unavoidably slow to load, you might feature a progress bar and perhaps some copy explaining (or even making light of) the long load time.

Benefits of web performance optimization

For businesses, the benefits of web performance optimization include: 

• Increased conversions: According to Unbounce, 70% of customers say page speed impacts their willingness to purchase from a retailer. 
• More visibility: Google’s PageRank algorithm—which ranks webpages based on quality and relevance—prioritizes site performance. Websites on the first page of Google results load in an average of 1.65 seconds. If organic search is part of your customer acquisition strategy, keep website speed top of mind. 
• Better usability: A faster and more responsive site can improve the overall user experience (UX), fostering customer satisfaction and confidence. 

How to measure your website performance

The first step to improving a website’s performance is to get baseline measurements to help inform your optimization efforts. You can use numerous tools for this, but popular options include Google PageSpeed Insights, GTmetrix, Lighthouse, WebPageTest, and YSlow—all are free or offer free options. You can also use Shopify web performance dashboard.

Key web performance optimization metrics include: 

Page load time

Page load time is the most widely used and the easiest metric to understand. It is the duration it takes for a webpage to fully load and become visible to a user in their browser. This includes the time it takes to retrieve all the necessary resources, like HTML, CSS, JavaScript, images, and other elements, from the server and render them on the device. 

Time to first byte (TTFB)

TTFB is the time it takes for the browser to receive the first byte of data from the server after sending a request. In general, a lower TTFB indicates a faster server response time and, as a result, a better user experience. 

Recently, we found the average Shopify site has a TTFB of 0.51 seconds. This is in stark contrast to sites on other platforms, which have an average TTFB of 1.51 seconds and up to 1.99 seconds. In plain terms, these stats show Shopify has the fastest server speed in commerce, on average by 2.8x and up to 3.9x faster. 

Want to read more about Shopify’s clear site speed advantage? Read the full report

Time to interactive (TTI)

TTI measures the time it takes for the webpage to become fully interactive and responsive to user input—the point at which they can effectively engage with the page (e.g., click buttons or enter data) without experiencing significant delays. 

Start render

Start render refers to the moment when the first visual elements of a webpage—including text, images, and other graphical elements—appear on the user’s screen.

Total page size

The total page size refers to the combined size, in bytes, of all the elements that make up the webpage (HTML, CSS, and JavaScript, as well as images, videos, and other resources). Minimizing the page size helps reduce the data transfer time and improves overall load times.

First contentful paint (FCP)

FCP measures the time it takes for the browser to render the first piece of content on the webpage, such as text or images. It represents the moment when users perceive the initial visual response. 

Largest contentful paint (LCP)

LCP measures the time it takes for the browser to render the most prominent visible element or content block, like an image or text block, providing insights into when the essential content becomes available to users. 

Total blocking time (TBT)

TBT represents the total time during page load when the main thread is blocked and unable to respond to user input. It measures the impact of resource-intensive operations or JavaScript execution on the ability to interact with the page.

Number of HTTP requests

This metric represents the total number of requests the browser makes to fetch the necessary resources for rendering the webpage. A lower number of HTTP requests is better for performance. 

Nine ways to optimize your website performance

1. Optimize image files
2. Minify and combine files
3. Use browser caching
4. Use content delivery networks (CDNs)
5. Optimize code execution
6. Enable gzip compression
7. Minimize redirects
8. Optimize third-party scripts and plugins
9. Monitor performance

Once you have data on your site’s current performance, you can start optimizing it. Here are nine impactful strategies to consider: 

1. Optimize image files

Images files can be huge, meaning a browser may take a long time to download them. You can compress images using online tools like TinyPNG or Compressor.io or resize them using editing software like Photoshop. Additionally, try only to include essential images. If it doesn’t have to be there, it may not be worth the extra bandwidth. 

2. Minify and combine files

Minification means reducing the size of source code by removing unnecessary characters and reducing the size of HTML, JavaScript, and CSS files. Combining multiple files into one reduces the number of requests the browser needs to make, speeding up the loading process. You can do this with tools like Webpack and Grunt. 

3. Use browser caching

Browser caching means some of your site’s resources—such as images, CSS, and JavaScript files—are stored in the user’s browser. This way, their browser doesn’t need to fetch your site’s files from the server every time they visit a page on your site, speeding up the loading process. Browser caching can be set up by setting “cache-control” and “expires” headers on the web server and then determining the duration files that will be stored in the user’s browser. 

4. Use content delivery networks

Content delivery networks (CDNs) store content from your website on servers located closer to each user’s geographical location, reducing the distance data needs to travel. CDNs minimize latency and improve load times. Popular CDNs include Cloudflare, Akamai, and Fastly.

To supplement our already strong points of presence in North America, Shopify expanded our fleet of Google Cloud servers to locations across Europe. Our fleet is supported by Cloudflare CDN, which has over 300 points of presence. This keeps brands closer to their customers, no matter where they are. 

5. Optimize code execution

Streamlining the code on your site can help browsers load it faster. For example, optimizing database queries can yield faster search functions, as it takes less time to retrieve results. You can streamline code to load the most important elements to the user—for example, prioritizing the content that first appears to the user before they scroll.

6. Enable gzip compression

Gzip is an algorithm that compresses text-based resources, such as HTML files, CSS files, and JavaScript files. It significantly reduces their file size, allowing for faster data transfer and page rendering. Most modern web servers have gzip support built in. It can be enabled by configuring the web server so it varies between servers. 

7. Minimize redirects

A redirect is when one URL is automatically routed to another—for example, when a URL for a defunct product sends users to a URL for a new product. In general, aim to minimize these, as they increase the time it takes to load a page. Keep the sitemap up to date to ensure users are directed to their intended destinations efficiently, and try to repurpose (rather than redirect) pages with high direct traffic.

8. Optimize third-party scripts and plug-ins

Most sites use a lot of plug-ins. These software components add features to a website and integrate easily with a content management system (CMS) or web framework. However, they can slow site performance. Speed up page loading by regularly removing unnecessary plug-ins you aren’t using.

9. Monitor performance

The last way to improve website performance is to keep an eye on it. Running regular performance tests is the best way to ensure long-term optimization. These efforts may take time, but they can yield a much faster site—and the improved conversions, page rank, and reputation that come with it. 

Earlier in 2024, Shopify announced our new web performance dashboard, which uses Google’s Core Web Vitals to give businesses a clearer picture of how their websites perform. Our previous Site Speed score used a single Lighthouse score to measure site performance, but that didn’t account for real-world user interactions. Google’s Core Web Vitals, however, are an industry-standard for measuring and optimizing the actual user experience.