In an age of instant access to information, every second spent waiting for a website to load costs you a potential customer. Google is well aware of this, which is why, since the Page Experience update, performance metrics have become a key element of the ranking algorithm. Understanding this, how to improve page loading speed, ... is no longer the preserve of programmers, but the cornerstone of effective online marketing in 2026.
What are Core Web Vitals and why do you need to know about them?
Core Web Vitals are a set of specific metrics that Google considers to be the most important for assessing the quality of the user experience (UX). They focus on three aspects: page load speed, interactivity and visual stability.
- LCP (Largest Contentful Paint): It measures the time it takes for the largest content element (e.g. the main image or header) to become visible. A good result is under 2.5 seconds.
- INP (Interaction to Next Paint): The successor to FID, which measures the delay in the page’s response to each click or tap by the user. A result of under 200 ms is ideal.
- CLS (Cumulative Layout Shift): A metric that measures how much page elements „jump” whilst loading (e.g. when an advert suddenly pushes down the text you’re reading). The score should be less than 0.1.
To diagnose your website, use the tool Google PageSpeed Insights, which will show you data based on actual user visits.
Graphics and multimedia – the most common cause of slowdowns
High-resolution images are the biggest „bandits” when it comes to page speed. Optimising the visual layer is the simplest way to significantly improve your LCP score.
How can I optimise images?
- Modern formats: Convert your old JPG and PNG files to WebP or AVIF formats, which offer much better compression whilst maintaining high quality.
- Lazy Loading: The implementation of the „lazy loading” technique ensures that the browser only loads the images that are currently within the user’s field of view.
- Responsive images: Serve smaller files to mobile users. There’s no point in sending a 3000-pixel-wide photo to a smartphone screen.
You can read more about these techniques in our guide: Optimising images on a website.
Technical code optimisation: CSS and JavaScript
When the browser encounters JavaScript scripts or CSS styles in the <head>, often delays the rendering of the page until they have been downloaded. These are known as render-blocking resources.
To improve speed, you should use minification (removing unnecessary spaces and comments from the code) and file concatenation. It is also crucial to load critical CSS code inline and the rest asynchronously. This allows the user to see the page structure almost immediately, even if advanced scripts are still loading.
If you're looking for free code analysis tools, check out our SEO tools – an overview of free options.
How can I stop my website from jittering (CLS)?
A high CLS score is the bane of websites with dynamic content. The most common cause is images and adverts without defined dimensions in the HTML code.
Practical solutions for website stability:
- Booking a place: Always specify the attributes
widthiheightfor images and ad containers. This allows the browser to „reserve” the space before the content is downloaded. - Web fonts: Use the properties
font-display: swap, to avoid the 'font on it' (FOIT) effect when loading custom fonts. - Avoiding dynamic content at the top: Please do not insert banners that appear over content that has already been read, pushing it further down the page.
Server, Cache and CDN
Even the best-written code won’t run quickly on a slow server. Server response time (TTFB) is the foundation of all other metrics.
- Implementation of a CDN (Content Delivery Network): Using services such as Cloudflare allows static website elements to be served from servers located closest to the user.
- Browser caching: Configure the server so that the browser caches certain elements (logos, styles) and does not have to download them every time a new page is loaded.
- HTTP/3 version: Make sure your server supports modern data transfer protocols, which are much more efficient on slower mobile connections.
You can find detailed technical guidelines at web.dev – Core Web Vitals.
A fast website means higher conversion rates
Investing in this, how to improve page loading speed, ... pays off not only in the form of higher rankings on Google, but above all in user satisfaction. Every 100 ms improvement in loading time can actually increase your online shop’s revenue.
At 4ADStudio, we carry out comprehensive performance audits, helping brands achieve „green results” in Lighthouse and PageSpeed Insights tests.
Is your website loading too slowly? Don’t let the competition get ahead of you. Get in touch with us and boost your business today!
