Fix The Largest Contentful Paint Image Was Lazily Loaded Warning

A survey by GoodFirms showed that 88.5% of visitors leave a website due to slow loading speed. In the quest for providing exceptional user experiences, optimizing the loading speed of your web pages is crucial. However, you may have come across a common warning message “Largest Contentful Paint image was lazily loaded.” This warning indicates that the most significant image on your page was slowly loaded, potentially affecting the overall performance and user engagement.

No more worry, because the intricacies of this warning and effective techniques to fix it will be introduced in this article. We will explore various strategies, from optimizing image loading to leveraging lazy loading techniques, to ensure that your website achieves faster and smoother loading times.

What Does It Mean By “Largest Contentful Paint Image Was Lazily Loaded”?

The Largest Contentful Paint (LCP) is a user-centric performance metric that measures the time it takes for the largest content element on a web page to become visible within the viewport. It is one of the Core Web Vitals, a set of metrics used to assess and quantify the user experience of web pages.

This metric focuses on the perceived loading speed and visual stability of a web page. It identifies the element that is most significant in terms of its size and impact on the user’s visual experience and reflects how quickly a user can see meaningful content on a webpage. A fast LCP ensures that users perceive the page as loading quickly and being visually complete.

When the warning states that the “largest contentful paint image was lazily loaded,” it means that the image identified as the largest and most significant element on the page was loaded using lazy loading techniques.

The warning message “largest contentful paint image was lazily loaded” can have several underlying causes. Here are some common factors that may trigger this warning:

• Lazy Loading Implementation: Lazy loading is designed to defer the loading of images until they are needed, typically when they are about to enter the viewport. However, if the implementation is not correctly configured or if lazy loading is applied to all images indiscriminately, including the largest contentful image, it can lead to a warning.
• Incorrect Image Sizing: When the dimensions (width and height) of an image are not explicitly specified in the HTML markup or are set to incorrect values, it can disrupt the calculation of the largest contentful paint. As a result, the browser may perceive the image as larger or smaller than it actually is, leading to the warning.
• Network or Server Delays: Slow network connections or delays in serving the image file from the server can also contribute to the warning. If the browser detects a significant delay in fetching or loading the largest contentful image, it may issue a warning to notify about potential performance issues.
• JavaScript Interference: If JavaScript code interferes with the lazy loading process or modifies the behavior of image loading, it can impact the timing and order in which images are loaded. This interference can trigger the warning message if the largest contentful image is not loaded in a timely manner.
• Third-Party Scripts or Plugins: The presence of third-party scripts or plugins on the webpage can introduce conflicts or inconsistencies with lazy loading implementations. These external components may affect the loading sequence of images, potentially resulting in the warning being triggered.

Why You Should Optimize Your Website’s LCP

LCP is indeed used by Google to evaluate a website’s performance

Google has placed increased emphasis on user experience and page performance, and as part of its efforts, it introduced Core Web Vitals as essential metrics for evaluating and improving website performance. LCP is one of the three key metrics included in Core Web Vitals, alongside First Input Delay (FID) and Cumulative Layout Shift (CLS).

Google considers LCP as a critical metric for determining the overall user experience of a webpage. If your website provides a fast and efficient user experience, with a low LCP, it is more likely to rank higher in search results and receive better visibility.

Page Load Speed ​​Affects SEO Ranking

Google has officially confirmed that page speed is a ranking factor in its search algorithm. The speed at which a webpage load has a direct impact on the user experience, and Google aims to provide the best possible experience to its users. Therefore, websites that load faster are generally rewarded with better rankings in search results. If the largest contentful image is lazily loaded, resulting in slower loading times and a less optimal user experience, it can potentially impact the website’s search engine rankings.

As one of the three factors that make up the page load speed metric, LCP directly affects the page load speed. It is now part of Google’s ranking algorithm, and sites that provide a better user experience in terms of page speed and other Site Vitals are more likely to rank higher.

Page crawling is hampered by slow loading

Slow loading can hamper page crawling by Google search engine bots. When a webpage takes a long time to load, search engine crawlers may not be able to access and crawl all the content effectively. This can result in incomplete indexing and potentially affect the visibility of your website’s pages in search results.

LCP helps measure the perceived loading speed and user experience related to the rendering of the primary content. A fast-loading LCP indicates that the main content of a webpage is quickly visible to users, leading to a better user experience. On the other hand, a slow LCP can result in a poor user experience, higher bounce rates, and potential ranking penalties.

Visitors value content

When the largest contentful image on a web page is loaded lazily, it can cause a delay in the rendering of critical visual content. This delay can result in a slower perceived loading speed for users and impact the overall user experience.

Interesting and engaging content is one of the top priorities of the LCP metric, so it’s your job to upgrade the quality of your site’s content to enhance your site’s appeal to users. This can prove to search engines that your website is a valuable and trusted source, thereby improving your rankings in search results.

LCP ensures a positive experience for visitors and effective absorption of content because it affects how fast the main content of the page loads. So optimizing for LCP speed will encourage users to read and engage with your content.

Increased Conversion Rates

Slow-loading web pages and poor user experiences can have a direct impact on conversion rates. If visitors have to wait for the largest contentful image to load or encounter visual inconsistencies, they may be more likely to abandon the website or not complete desired actions such as making a purchase or filling out a form.

A faster LCP and more user-friendly website tends to have higher conversion rates. There is a strong correlation between page load speed and user behavior, including conversion rates. A study by Renault concluded that a one-second improvement in LCP led to a 14% lower bounce rate and a 13% increase in conversions.

Faster LCP reduces the time users spend waiting for the main content to load. This helps to capture and maintain user attention, increasing their engagement with the website. Users are more likely to stay longer, interact with more content, and ultimately convert. By reducing any potential frustration or impatience caused by slow-loading content, a faster LCP can lead to higher engagement and conversion rates.

Furthermore, a fast-loading LCP reduces bounce rates as users quickly access the desired content, encouraging them to stay on the website and potentially convert.

8 effective methods to fix the “largest contentful paint image was lazily loaded” warning

To fix the “largest contentful paint image was lazily loaded” problem and ensure optimal loading of the largest contentful image on your website, you can employ the following methods:

Optimize Image Loading

Properly optimize your images to reduce their file size without sacrificing quality. Choose the appropriate image format based on the content. For graphics or images with fewer colors, use PNG or SVG formats. For photographs or images with many colors, JPEG format is more suitable. Using the right format ensures optimal image quality and smaller file sizes.

Compress your images to reduce their file size without significant loss in quality. You can use image compression tools like TinyPNG, JPEGmini, or ImageOptim to optimize your images before uploading them to your website. Compressed images load faster, resulting in improved page load speed.

Set Explicit Image Dimensions

Specify the width and height attributes of the largest contentful image in the HTML markup. This allows the browser to reserve the necessary space for the image and avoid layout shifts when it loads.

Prioritize Critical Images

Arrange your HTML markup and CSS to ensure that the LCP image is loaded early in the page’s rendering process. This way, the LCP image is prioritized and appears quickly, providing users with meaningful content while other images load lazily.

If you have control over the HTML structure, you can include the LCP image in the HTML markup with appropriate dimensions and use CSS to hide it initially. Then, leverage JavaScript to preload the LCP image in the background before revealing it to users. This way, the LCP image is loaded and ready to display without relying on lazy loading.

There are some tools to help you:

• WebPageTest: (https://www.webpagetest.org/) Use the filmstrip view to pin down the exact moment your largest image becomes visible.
• Chrome DevTools Performance Tab: Record a page load and analyze the LCP element in the Timings section.
• PageSpeed Insights: (https://developers.google.com/speed/pagespeed/insights/) Analyzes your site and identifies the LCP element.

Avoid Overusing Lazy Loading

While lazy loading is an effective technique to improve page load speed, it’s essential to use it judiciously and avoid overusing it for the largest contentful image. By loading the LCP image immediately, you ensure that users see the most important content right away. Reserve lazy loading for other non-LCP images on the page.

Consider applying lazy loading to images that appear below the initial viewport or as users scroll down the page. This way, images outside the immediate view are loaded only when needed, improving performance without affecting the LCI.

Use Intersection Observer

Implement the Intersection Observer API to monitor when the largest contentful image enters the viewport.  By setting up the observer to monitor images outside the initial view, you can selectively apply lazy loading based on their visibility. When it is about to become visible, trigger the image loading to ensure timely and efficient rendering.

Minimize JavaScript Impact

Review and optimize your JavaScript code to make it more efficient and reduce its impact on page loading. Identify any unnecessary or redundant code and eliminate it. Optimize loops, conditional statements, and resource-intensive operations to improve overall performance.

Consider these tools:

• Identify Bottlenecks:
  • Chrome DevTools Performance Tab: Analyze your JavaScript execution timeline to pinpoint long-running tasks or functions that delay rendering.
  • Lighthouse Audit (in DevTools): Get specific recommendations under the “Performance” section on how to reduce JavaScript’s impact.
• Minification:
  • Online Tools: Minify your JavaScript files to remove unnecessary characters using tools like UglifyJS (https://skalman.github.io/UglifyJS-online/) or Closure Compiler (https://closure-compiler.appspot.com/home)
  • Build Tools: Automate minification with Webpack, Gulp, or similar task runners.
• Optimize Code:
  • Efficient Algorithms: Choose efficient data structures and algorithms.
  • Reduce DOM Manipulation: Minimize direct DOM manipulation using techniques like event delegation.
  • Libraries/Frameworks: Use lightweight alternatives for smaller projects or when you need only specific functionalities.

Load JavaScript files asynchronously using the “async” attribute or dynamically load them via JavaScript. This allows the LCP image and other critical resources to load without being blocked by JavaScript files. However, be cautious with asynchronous loading to ensure that it doesn’t interfere with the required functionality of your website.

Evaluate Third-Party Scripts and Plugins

Review the impact of third-party scripts and plugins on your lazy loading implementation. Ensure they are not conflicting with or impeding the loading of the largest contentful image. Consider removing or optimizing any unnecessary or resource-heavy components.

Test and Monitor Performance

Regularly test and monitor your website’s performance using tools like Google PageSpeed Insights, Lighthouse, or WebPageTest. These tools can provide insights into loading issues, including the largest contentful paint, and help you identify areas for further optimization.

Conclusion

In conclusion, optimizing the loading speed of your web pages is crucial for providing exceptional user experiences. The Largest Contentful Paint (LCP) metric plays a vital role in evaluating the loading speed and visual stability of a webpage. When the largest contentful image is lazily loaded, it can negatively impact performance, user engagement, and SEO.

By following the above strategies, you can address the “largest contentful paint image was lazily loaded” warning and ensure that your website achieves faster and smoother loading times, leading to improved user experiences, increased engagement, and better SEO performance.