Speed, Performance, and Core Web Vitals

Chapter 6: Unit 2: Speed, Performance, and Core Web Vitals

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In this unit, we will explore the importance of speed and performance in relation to SEO, as well as the concept of Core Web Vitals. We will delve into various aspects of optimizing website speed, measuring performance metrics, and understanding the impact of Core Web Vitals on search engine rankings.

1. Why is website speed crucial for SEO?

Website speed plays a critical role in SEO because it directly impacts user experience, search engine rankings, and overall website performance. A slow-loading website can lead to higher bounce rates, reduced user engagement, and lower conversions. Additionally, search engines like Google have explicitly stated that page speed is a ranking factor, making it essential to optimize website speed for better SEO outcomes.

For example, let’s consider an e-commerce website that sells clothing online. If the website takes too long to load, potential customers may become impatient and abandon the site, resulting in lost sales opportunities. On the other hand, a fast-loading website provides a seamless browsing experience, keeping users engaged and increasing the likelihood of conversions.

2. What are some common factors affecting website speed?

Several factors can affect website speed. Here are a few key elements to consider:

• Server performance: The quality and efficiency of the web hosting server can significantly impact website speed. A slow or overloaded server may cause delays in delivering web pages to users.
• Large file sizes: Images, videos, and other media files that are not properly optimized can contribute to slow page loading times. Compressing images and using appropriate file formats can reduce file sizes.
• Code optimization: Poorly written or bloated code can slow down a website. Minifying CSS and JavaScript files, removing unnecessary code, and optimizing HTML can improve page load speed.
• Browser caching: Implementing browser caching allows browsers to store certain website elements locally, reducing the need to download them with each page visit. This significantly speeds up subsequent page loads for returning visitors.
• Content delivery network (CDN): Utilizing a CDN helps distribute website content across multiple servers worldwide, ensuring faster delivery to users in different geographic locations.

3. What are Core Web Vitals, and how do they relate to SEO?

Core Web Vitals are a set of specific metrics that measure different aspects of user experience on websites. They focus on three key factors: loading, interactivity, and visual stability. The metrics associated with Core Web Vitals are:

• Largest Contentful Paint (LCP): LCP measures the time it takes for the largest element of a web page to become visible to the user. It indicates how quickly the main content appears on the screen.
• First Input Delay (FID): FID measures the time it takes for a web page to respond to a user’s first interaction, such as clicking a button or selecting a menu item. It reflects the interactivity and responsiveness of the website.
• Cumulative Layout Shift (CLS): CLS measures the amount of unexpected layout shifts that occur during the loading process. It quantifies the visual stability of a webpage, ensuring that elements do not move unexpectedly.

These Core Web Vitals metrics are crucial for SEO because they provide insights into the user experience. Google has indicated that starting from May 2021, Core Web Vitals will be factored into the search ranking algorithm. Websites that deliver a better user experience, as indicated by strong Core Web Vitals performance, may receive a ranking boost.

4. How can website owners optimize for Core Web Vitals?

To optimize for Core Web Vitals, website owners should focus on improving the metrics associated with LCP, FID, and CLS. Here are some strategies to consider:

• Optimize server response time: Ensure your server responds quickly to requests by leveraging caching, server-side optimizations, and a reliable hosting provider.
• Compress and optimize images: Reduce image file sizes without compromising quality using compression techniques or using modern image formats such as WebP.
• Minimize render-blocking resources: Identify and eliminate or defer render-blocking JavaScript and CSS to allow the browser to start rendering the page faster.
• Prioritize above-the-fold content: Ensure that the main content of the page, also known as above-the-fold content, loads quickly to improve LCP.
• Optimize JavaScript execution: Minify JavaScript files, eliminate unused code, and consider code splitting or lazy loading to improve FID.
• Avoid layout shifts: Reserve space for dynamic elements, provide dimensions for images and videos, and use CSS properties that prevent sudden layout shifts to improve CLS.

By implementing these optimizations, website owners can enhance Core Web Vitals performance, improve user experience, and potentially achieve higher search engine rankings.

5. Are there any tools available to measure and monitor Core Web Vitals?

Yes, there are several tools available to measure and monitor Core Web Vitals. Here are a few popular options:

• Google PageSpeed Insights: This tool provides insights into various performance metrics, including Core Web Vitals. It offers recommendations for improvement and assigns a score based on performance.
• Google Search Console: The Core Web Vitals report in Google Search Console helps website owners monitor their website’s performance and identify pages with poor Core Web Vitals metrics.
• Lighthouse: Lighthouse is an open-source tool that runs as a browser extension or from the command line. It audits web pages for performance, accessibility, SEO, and more, including Core Web Vitals.
• Web.dev: This online resource from Google offers detailed guides and tools to improve website performance, including Core Web Vitals analysis.

Using these tools, website owners can identify areas for improvement, track progress over time, and ensure their websites provide a positive user experience based on Core Web Vitals metrics.

Overall, understanding the significance of website speed, optimizing performance, and prioritizing Core Web Vitals are essential steps for achieving better SEO rankings and delivering an excellent user experience.

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Page Speed Insights and Speed Optimization

Page speed is one of the most important factors that affect the user experience and the performance of a website. Page speed refers to how fast a web page loads and displays its content to the user. A faster page speed can improve user satisfaction, engagement, conversion, and retention. A slower page speed can lead to user frustration, bounce, abandonment, and loss of revenue.

Google PageSpeed Insights (PSI) is a tool that helps you measure and optimize your page speed for both mobile and desktop devices. PSI analyzes your web page and provides you with a score and a list of suggestions on how to improve your page speed. PSI also provides you with both lab and field data about your page speed.

Lab data is collected by running a series of tests on a simulated environment using a predefined device and network settings. Lab data can help you identify potential performance issues and opportunities for improvement. However, lab data may not reflect the real-world conditions and experiences of your users.

Field data is collected by measuring the actual performance of your web page on real devices and networks used by real users. Field data can help you understand how your web page performs in the wild and how it affects your user satisfaction and business outcomes. However, field data may not be available for all pages and may vary depending on various factors.

How to Improve Your Google PageSpeed Insights Score

To improve your Google PageSpeed Insights score, you need to follow the suggestions provided by the tool based on your web page analysis. The suggestions are categorized into three types:

•  Opportunities: These are suggestions that can help you improve your page speed by reducing the amount of time it takes to load the main content of your page. These suggestions usually have the most impact on your score and user experience.

•  Diagnostics: These are suggestions that can help you improve your page speed by providing additional information about how your page adheres to best practices for web performance. These suggestions usually have less impact on your score but can still improve your user experience.

•  Passed audits: These are suggestions that you have already implemented or do not apply to your page. These suggestions indicate that your page follows some of the best practices for web performance.

Some of the common suggestions that can help you improve your page speed are:

1. Eliminate Render-Blocking Resources

Render-blocking resources are resources that prevent the browser from rendering the content of your web page until they are loaded. These resources usually include CSS and JavaScript files that are linked in the head section of your HTML document.

To eliminate render-blocking resources, you can use one or more of the following techniques:

•  Inline critical CSS: This means embedding the CSS code that is essential for rendering the above-the-fold content of your web page directly into your HTML document. This can reduce the number of requests and avoid blocking the rendering of your page.

•  Defer non-critical CSS: This means delaying the loading of CSS code that is not essential for rendering the above-the-fold content of your web page until after the initial render. This can be done by using the rel=”preload” attribute or the media=”print” attribute on your link tags, or by using JavaScript to dynamically load the CSS files.

•  Minify CSS: This means removing unnecessary whitespace, comments, and other characters from your CSS code to reduce its size and improve its loading time.

•  Inline critical JavaScript: This means embedding the JavaScript code that is essential for rendering the above-the-fold content of your web page directly into your HTML document. This can reduce the number of requests and avoid blocking the rendering of your page.

•  Defer non-critical JavaScript: This means delaying the loading of JavaScript code that is not essential for rendering the above-the-fold content of your web page until after the initial render. This can be done by using the async or defer attributes on your script tags, or by using JavaScript to dynamically load the script files.

•  Minify JavaScript: This means removing unnecessary whitespace, comments, and other characters from your JavaScript code to reduce its size and improve its loading time.

2. Reduce Server Response Times (TTFB)

Server response time (TTFB) is the time it takes for the server to respond to a request from the browser. A high server response time can delay the loading of your web page and affect your user experience.

To reduce server response time, you can use one or more of the following techniques:

•  Optimize your server configuration: This means ensuring that your server has enough resources (CPU, memory, disk space, etc.) to handle the incoming requests efficiently. You can also use caching, load balancing, compression, and other techniques to improve your server performance.

•  Optimize your database queries: This means ensuring that your database queries are fast and efficient, and that they do not fetch more data than necessary. You can also use indexing, caching, pagination, and other techniques to improve your database performance.

•  Optimize your application code: This means ensuring that your application code is well-written, organized, and optimized for performance. You can also use frameworks, libraries, and tools that can help you speed up your development and deployment process.

3. Properly Optimize Your Images

Images are one of the most common and impactful resources on your web page. However, images can also be one of the most heavy and slow-loading resources if they are not properly optimized.

To properly optimize your images, you can use one or more of the following techniques:

•  Resize your images: This means ensuring that your images are not larger than they need to be for displaying on your web page. You can use tools like Photoshop, GIMP, or online image resizers to resize your images to the appropriate dimensions.

•  Compress your images: This means reducing the file size of your images without compromising their quality. You can use tools like TinyPNG, JPEGmini, or online image compressors to compress your images to the optimal level.

•  Choose the right image format: This means selecting the image format that is best suited for your web page and your image content. You can use formats like JPEG, PNG, WebP, or SVG depending on the type and quality of your images.

•  Use responsive images: This means using different versions of your images for different screen sizes and resolutions. You can use techniques like srcset, sizes, or picture elements to provide the browser with the best image option for each device.

4. Avoid Chaining Critical Requests

Chaining critical requests is a situation where one resource depends on another resource to load before it can load itself. This can create a cascade of delays and affect the loading time of your web page.

To avoid chaining critical requests, you can use one or more of the following techniques:

•  Preload key requests: This means instructing the browser to fetch certain resources as soon as possible, even before they are needed by the web page. This can reduce the waiting time and improve the loading time of your web page. You can use the rel=”preload” attribute on your link or script tags to preload key requests.

•  Prefetch key requests: This means instructing the browser to fetch certain resources in advance, even before they are needed by the web page. This can improve the loading time of your web page when the user navigates to another page that requires those resources. You can use the rel=”prefetch” attribute on your link or script tags to prefetch key requests.

•  Use HTTP/2: This means using the latest version of the HTTP protocol that supports multiplexing, which allows multiple requests and responses to be sent over a single connection. This can reduce the number of connections and requests needed to load your web page and improve its loading time.

5. Reduce CSS and JavaScript

CSS and JavaScript are essential for creating dynamic and interactive web pages. However, too much CSS and JavaScript can also slow down your web page and affect its performance.

To reduce CSS and JavaScript, you can use one or more of the following techniques:

•  Concatenate CSS and JavaScript: This means combining multiple CSS and JavaScript files into one file to reduce the number of requests and improve its loading time.

•  Remove unused CSS and JavaScript: This means removing any CSS and JavaScript code that is not used by your web page to reduce its size and improve its loading time.

6. Defer Offscreen Images

Offscreen images are images that are not visible to the user until they scroll down or sideways on your web page. Loading offscreen images can consume bandwidth and resources that could be used for loading other critical resources on your web page.

To defer offscreen images, you can use one or more of the following techniques:

•  Lazy load offscreen images: This means delaying the loading of offscreen images until they are near or in the viewport of the user. This can reduce the initial loading time of your web page and improve its performance. You can use techniques like loading=”lazy” attribute, Intersection Observer API, or JavaScript libraries to lazy load offscreen images.

•  Use placeholders for offscreen images: This means using low-quality or low-resolution versions of your offscreen images as placeholders until they are fully loaded. This can improve the perceived loading time of your web page and provide a better user experience. You can use techniques like progressive JPEGs, blurred backgrounds, or skeleton screens to create placeholders for offscreen images.

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Topic 2: Mobile Performance

Why is Mobile Performance Important for SEO?

Mobile devices have become an integral part of our daily lives, and an increasing number of people are using their smartphones and tablets to browse the internet. In fact, mobile searches have surpassed desktop searches in recent years. This shift in user behavior has led search engines like Google to prioritize mobile-friendly websites and consider mobile performance as a ranking factor.

How Does Mobile Performance Impact User Experience?

Mobile performance plays a crucial role in determining the user experience on a website. Users expect fast and seamless browsing experiences on their mobile devices, and a slow-loading or poorly-performing website can lead to frustration, increased bounce rates, and decreased user engagement.

For example, imagine you’re searching for a recipe on your smartphone, and you click on a link that takes too long to load. Chances are, you would abandon that website and look for an alternative that provides a better user experience. This highlights the importance of mobile performance in keeping users engaged and satisfied.

How Does Mobile Performance Affect Search Rankings?

Search engines, especially Google, have recognized the significance of mobile performance in delivering a positive user experience. As a result, they have incorporated mobile-friendliness and mobile performance as ranking factors in their search algorithms.

Websites that load quickly and provide a seamless experience on mobile devices are more likely to rank higher in search engine results pages (SERPs). Google has even introduced the Mobile-First Indexing approach, where the mobile version of a website is considered the primary version for indexing and ranking. This shift emphasizes the need for websites to prioritize mobile performance to maintain or improve their search rankings.

Strategies for Optimizing Mobile Performance

Now that we understand the importance of mobile performance in SEO, let’s explore some strategies and best practices for optimizing the performance of websites on mobile devices.

Optimize Page Speed for Mobile Devices

Page speed is a critical factor for mobile performance. It is clear to you now slow-loading web pages lead to higher bounce rates and lower user engagement. To optimize page speed for mobile devices, consider the following:

• Compress and optimize images: Reduce the file size of images without compromising quality. Use image compression techniques and formats that are suitable for mobile devices, such as WebP.
• Minify CSS, JavaScript, and HTML: Remove unnecessary characters, spaces, and line breaks from your code to reduce file sizes. This helps to improve page load times.
• Enable browser caching: Leverage browser caching to store static resources locally on the user’s device. This reduces the need for repeated downloads and improves subsequent page loads.
• Implement lazy loading: Load images and other non-critical resources only when they become visible to the user. This technique helps to prioritize the loading of important content and speeds up overall page rendering.

Let’s consider an e-commerce website that sells clothing. The website is designed to be responsive and mobile-friendly, but the pages take a long time to load on mobile devices. By implementing the strategies mentioned above, such as compressing images, minifying code, and enabling browser caching, the website can significantly improve its mobile performance. As a result, users will experience faster page load times, leading to higher engagement, increased conversions, and potentially better search rankings.

Design for Mobile Usability

Usability is a crucial aspect of mobile performance. Designing your website with mobile users in mind ensures that visitors can easily navigate, interact with, and consume your content on smaller screens. Consider the following best practices for mobile usability:

• Responsive design: Create a responsive website that adapts to different screen sizes and resolutions. This ensures that your content is accessible and well-presented on various mobile devices.
• Intuitive navigation: Simplify your website’s navigation for mobile users. Use clear and concise menus, sticky headers, and intuitive gestures to make it easy for users to find what they’re looking for.
• Readable font sizes: Use legible font sizes and adjust them for mobile screens. Small text sizes can strain users’ eyes and make it difficult to read content.
• Optimize forms and inputs: Streamline forms and input fields for mobile users. Use input types and attributes optimized for mobile devices, such as email, number, and date inputs, and provide autocomplete suggestions where applicable.

Optimize Mobile Site Structure

Consider the following strategies for optimizing mobile site structure:

• Prioritize important content: Place the most important content, such as headlines, key information, and calls to action, at the top of the page. This ensures that users can quickly access and engage with essential elements without the need for excessive scrolling.
• Avoid intrusive interstitials: Intrusive interstitials, such as full-screen pop-ups or ads, can disrupt the user experience on mobile devices. Google specifically penalizes websites that display intrusive interstitials by downgrading their mobile search rankings. Use less obtrusive alternatives, such as banner notifications or inline calls to action.
• Implement a mobile-friendly menu: Design a mobile menu that is easy to access and navigate. Consider using a hamburger menu or collapsible menus to save screen space and provide a seamless browsing experience.
• Optimize touch targets: Ensure that clickable elements, such as buttons and links, have an appropriate size and spacing to accommodate touch inputs accurately. This prevents users from accidentally tapping the wrong elements and enhances overall mobile usability.

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Topic 3: Core Web Vitals as a Ranking Signal

1. Understanding Core Web Vitals

Since it has been discussed above, now let’s go a little deeper. Core Web Vitals refer to a set of specific website performance metrics that focus on three crucial aspects of user experience: loading speed, interactivity, and visual stability. These metrics help evaluate and measure how well a web page performs in delivering a seamless and user-friendly browsing experience. The three Core Web Vitals metrics are:

Largest Contentful Paint (LCP)

Largest Contentful Paint measures the time it takes for the largest content element on a web page to become visible to the user. It indicates how quickly the main content of a page is rendered.

LCP is a key metric to measure perceived load speed. The recommended benchmark for LCP is less than 2.5 seconds. A faster LCP ensures that users can access the most important information without any frustrating delays.

Example: Let’s say you have an e-commerce website selling clothing. When a user visits your product page, the LCP metric measures the time it takes for the product image and description to load and become visible. If it takes too long for the LCP to occur, the user might become frustrated and leave the page, leading to a potential loss of sales.

First Input Delay (FID)

First Input Delay measures the time between a user’s first interaction (such as clicking a button or selecting a menu item) and the browser’s response to that interaction. FID quantifies the responsiveness of a web page and reflects how quickly users can interact with the page.

The recommended benchmark for FID is less than 100 milliseconds. A lower FID ensures a smooth and interactive user experience.

Example: Imagine you visit a news website and want to read an article. If you click on a link to view the full article and there is a significant delay before the page responds to your click, it results in a poor FID score. Users expect websites to be responsive, and a slow FID can lead to frustration and abandonment.

Cumulative Layout Shift (CLS)

Cumulative Layout Shift measures the visual stability of a web page during the loading process. It quantifies the amount of unexpected layout shifts that occur while the page is rendering. A layout shift happens when elements on a page move or shift unexpectedly, often causing buttons or links to be clicked accidentally. The recommended benchmark for CLS is less than 0.1. A lower CLS ensures that users have a consistent and uninterrupted browsing experience.

Example: Suppose you are reading an article on a blog, and as the page loads, an image or an ad suddenly appears, pushing the text down. If this unexpected shift happens while you are about to click a link, it can be frustrating and disruptive to your reading experience. A low CLS score indicates that the page’s layout remains stable, improving user satisfaction.

2. The Importance of Core Web Vitals for SEO

Core Web Vitals matter for SEO because they reflect the user experience of a website. Google aims to provide users with the best possible search results, and user experience is a critical factor in achieving that goal. By using Core Web Vitals as a ranking signal, Google encourages website owners to prioritize user-centric performance and create websites that load quickly, respond to user interactions promptly, and maintain visual stability.

When your website provides a positive user experience by meeting the Core Web Vitals benchmarks, it is more likely to rank higher in search engine results. Google considers user experience as an essential ranking factor because it wants to direct users to websites that deliver a smooth and enjoyable browsing experience. Therefore, optimizing your website’s Core Web Vitals can lead to improved visibility, increased organic traffic, and ultimately, better conversions.

3. Strategies to Optimize Core Web Vitals

Optimizing Core Web Vitals requires a combination of technical optimizations and best practices to enhance your website’s performance. Here are some strategies and techniques you can employ to improve each of the Core Web Vitals metrics:

Note: While reading, it may seem that these words have been said above. In fact, everything is connected to everything. It sounds almost the same but there are some changes. And since you are an SEO expert, these tasks will be done by a web developer, so these tasks are not really yours to do. So all the things are expressed in this way so that they go deep into your mind.

Optimizing Largest Contentful Paint (LCP)

• Compress and optimize images: Resize and compress images to reduce their file sizes without compromising quality. Use modern image formats like WebP and employ lazy loading techniques to ensure images are loaded only when needed.
• Minimize render-blocking resources: Identify and address render-blocking CSS and JavaScript that delay the rendering of the main content. Optimize CSS delivery and leverage techniques like asynchronous loading and deferred JavaScript execution.
• Use a content delivery network (CDN): Utilize a CDN to distribute your website’s content across multiple servers worldwide, reducing latency and improving LCP by serving content from the nearest server to the user.

Optimizing First Input Delay (FID)

• Optimize JavaScript execution: Minimize long-running JavaScript tasks and remove any unnecessary JavaScript. Split large JavaScript files into smaller, more manageable chunks and load them asynchronously to prevent blocking user interactions.
• Prioritize critical resources: Load essential resources first to ensure that user interactions are not delayed. Use resource hints like preload and prefetch to prioritize critical assets and improve FID by proactively loading necessary resources.
• Optimize third-party scripts: Evaluate the impact of third-party scripts on FID and consider delaying or loading them asynchronously to avoid blocking user interactions.

Optimizing Cumulative Layout Shift (CLS)

• Set dimensions for media elements: Reserve appropriate space for images, videos, and other media elements by specifying their dimensions in the HTML. This prevents sudden layout shifts caused by delayed loading or dynamic content.
• Avoid inserting content dynamically: Ensure that elements do not appear unexpectedly or cause layout shifts due to late rendering. Use appropriate loading placeholders or reserve space for dynamic content in advance.
• Use CSS animations carefully: Animate elements with caution to prevent excessive layout shifts. Specify animation dimensions and transitions explicitly, and avoid abrupt changes in size or position that could disrupt the user’s browsing experience.

By implementing these optimization strategies, you can positively impact your website’s Core Web Vitals metrics, leading to an improved user experience and potentially better search engine rankings.

Outro

In this unit, you learned about speed, performance, and core web vitals, and how they affect your site’s technical SEO.

You also learned how to use Page Speed Insights and other tools to measure and optimize your site’s speed and performance. You also learned how to improve your mobile performance and user experience, how core web vitals are used as a ranking signal by Google, and how to improve them.

In the next unit, you will learn about security and accessibility, and how they impact your site’s technical SEO.

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Go to: Chapter 6 – Unit 1 – Unit 2 – Unit 3 – Chapter 7