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Henny Kel
Henny Kel

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How to Optimize Website for Core Web Vitals--A Guide for Designers

You have created a unique website for your business with great visuals and text. But even that is no guarantee of the website working well to drive traffic, which is crucial for business growth. What is most important now is that you take into account your users' experience. In other words, you should evaluate your website from the users' perspective, which is about keeping your core web vitals healthy.

And you better start thinking in terms of core web vitals since these are now the new set of parameters that Google has come out to rank websites on search results.

From June 2021, Google will use Core Web Vitals for ranking of websites. So, the old-fashioned SEO is not enough, and instead, as a web designer, you should now pay attention to optimizing the core web vitals.

What are Core Web Vitals?

Core Web Vitals from Google are the new measures to determine the level of user experience while being on the web. So, it is about the experience of a website’s users rather than how much time a website takes to load.

The Core Web Vitals parameters judge a website on how quickly users can interact with its pages.

Google has laid down three Core Web Vitals: Largest Contentful Paint (loading performance), Cumulative Layout Shift (visual stability), and First Input Delay (interactivity). Google considers these as the most critical metrics for user experience.

Largest Contentful Paint (LCP)

The LCP lets you know how much time your website's hero content or image takes to load from users' perspectives. For example, if users cannot see your most important image, including your custom logo, on your website, they get frustrated. If you do not have a custom logo or looking to redesign your logo, it is suggested to use an online logo maker tool to create & customize your logo or get a new one!
So, a good LCP time to load is less than or equal to 2.5 seconds. But if it is less than or equal to 4.0 seconds, then it needs improvement. If it takes more than 4.0 seconds to load, it is a poor user experience.

Cumulative Layout Shift (CLS)

The Cumulative Layout Shift (CLS) is about a website's layout shift, which results in a terrible user experience. When content is loading, some of the website's elements shift or move around. For example, you can't click on CTA because it has moved somewhere else or as your site loads ads, it keeps shifting the content around.

According to Google, CLS scores less than or equal to 1.0 seconds are good scores and excellent user experience. But if it is less than or equal to 0.25 seconds, it requires improvements, and more than 0.25 seconds is a poor score.

First Input Delay (FID)

The First Input Delay is the time between the user clicking on something on your website and the site responding to show that content. Since this aspect of content is heavily done and affected by Java Script, it is a complicated measure.
A good FID score is less than or equal to 100 ms. But less than or equal to 300 ms requires improvement, and more than 300 ms is a poor user experience.

Tips to optimize a website for Core Web Vitals

Here are some essential tips you should consider to improve your Core Web Vitals

Optimize your JavaScript execution

Check your FID score, and if it is poor, then it means you should be optimizing your JavaScript execution. This measure will help reduce the time between your browser execution JS code and your page.

To reduce the execution, you should defer unused JS, which you can find out easily. First, press the right mouse click when visiting your website and go to the ‘Inspect’ button. Then, go to the ‘Sources’ and find the three dots on the bottom. You can then add a tool called ‘Coverage’ and then go for the load function. You will then find out the JavaScript unused on your website page.
After you have found the unused JS, reduce it by code splitting. You should distribute one JS bundle, which are combined files, and turn them into small pieces.

Compress images to improve the loading speed

If your website design uses multiple images, consider compressing them to optimize your Core Web VItals. By compressing the images, you will make your website pages much lighter and reduce page size, which improves page loading speed and user experience. This measure should improve your LCP score.
Also, when you compress images, you will activate Content Delivery Network [ CDN] for your images. Note that CDN is a network of servers for users across the world. So, when you compress images, a server closest to the users can fast load images and pages.

Use lazy loading

If your site’s LCP score is poor, you can improve it by using lazy loading, computer programming for website design and development. Lazy loading helps keep a website’s loading speed when the user is scrolling down the page.
In this way, your LCP scores are always excellent. Also, it will help in limiting your bandwidth usage and your site’s SEO. Consequently, it is a good measure also to reduce your site’s bounce rate.
Lazy loading is beneficial for websites having animations, many images, or videos.

Ensure a better server response time

Your browser should receive content immediately from the server. Bit if it takes a longer time, it will delay showing up the heavy content such as infographics. As a result, your SEO and UX will be on the negative side. So, if you want to improve your LCP score and page-load metric, then pay attention to the ways to make your server respond quickly.

To find out your server response time, you should use First Byte [TTFB], which shows calculates the time a user will take to receive the first byte of your page content.
At the same time, do not forget first to ensure that your web hosting service is fast and you use CDN for your website. You should also review your plugins as they make your page heavier. So, keep only the plugins that are essential to your business.

Pay attention to images and embeds sizes.

If your CLS score is poor, visit your images and embeds sizes to correct their dimensions. The score might be poor due to the wrong dimensions of images, ads, or embeds in the CSS file. You should set their width and height properly so that your browser can allocate the right amount of space on your website page when some element is loading.
Make sure also that embeds such as YouTube videos on your web page are of correct dimensions. The default size of the video might be too big for your site page, and you need to resize it.
To resize the video, go to YouTube and open the video you want to use on your website, and then by clicking the share button go to the option <> Embed. Then, copy the code you get into your site’s back-end to change the video dimensions.

Wrapping Up

Google will now be ranking websites on the new Core Web Vitals such as the LCP, CLS, and FID. To optimize your website, you need to optimize your JavaScript execution, compress images on your site, use lazy loading, ensure better server response time and use the proper sizes of images and videos.

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