Why site speed matters for SEO and sales

They are three concrete measures of user experience Google tracks: LCP (Largest Contentful Paint) — how fast the main, largest visible element of the page appears (usually a heading or image); CLS (Cumulative Layout Shift) — how stable the page is while loading, i.e. whether elements "jump" and shift while you try to click something; and INP (Interaction to Next Paint) — how fast the page reacts when you click or tap something.

Google doesn't take these measures from lab tests but from real visits of real users (via the Chrome browser), and uses that data in ranking. Practically: if the site loads fast, doesn't "jump" while loading, and reacts immediately to touch, both visitors and Google's algorithm are happy.

You can check these measures for free through Google PageSpeed Insights or Search Console — enter the site address and get concrete numbers and recommendations for what slows down your specific page.

The most common culprit is images — a photo straight from a phone or a professional camera can be several megabytes, while the page needs only a fraction of that resolution for on-screen display. Without optimisation, each such image adds seconds of loading.

The second common problem is redundant add-ons and scripts — WordPress sites in particular tend to accumulate dozens of plugins, each adding its own code the browser must load and execute, even if the user never uses that feature.

The third problem is bad hosting — cheap shared hosting means your site shares server resources with hundreds of other sites, so when the others are under load, yours becomes slow too, no matter how optimised its own code is.

The fourth, less often mentioned problem: fonts. Loading too many different fonts or font weights (bold, light, italic each separately) slows down text display, especially on a slower mobile network.

Image optimisation: modern formats (WebP, AVIF) are considerably smaller than classic JPEG or PNG at the same visual quality, and images are delivered at the exact size the user's screen needs, not at the original's full resolution.

Clean code and a modern framework (like Next.js, which we use): only what is really needed for that page loads, instead of pulling in a whole code library every time for features not even used on that page.

Caching and a CDN (Content Delivery Network): content is delivered from the server physically closest to the user — a visitor from Banja Luka gets the site from a server in the region, not from another continent, which measurably reduces loading time.

Fewer heavy third-party scripts: every additional analytics tool, chat widget or marketing integration adds code that must load — it is useful to periodically reassess whether you really need each of them.

Server-side rendering and prerendering: the page is prepared in advance on the server instead of the user's browser having to assemble the content from scratch on every visit.

More than half of visits to most sites today come from phones, often over a mobile network slower and less stable than home internet. A site that "works fine" on fast office internet can be frustratingly slow for someone browsing on their phone while waiting at a traffic light.

That is why speed testing must include simulating a slower network, not just measuring on the fastest possible connection — the real picture of user experience comes only when you test the conditions in which visitors actually use the site.

The biggest mistake is treating speed as something to "optimise at the end", after the site is already built. By then, choices have been made (heavy animated elements, too many fonts, unoptimised images dropped straight from a folder) that are expensive and hard to reverse.

Instead, we build speed in from the first line of code: image optimisation is part of the publishing process, not an afterthought; technology is chosen with performance in mind; and every new feature is also assessed by how much it adds to loading time.

A fast site ranks better on Google, converts more visitors into inquiries or purchases, and is cheaper to advertise because fewer people abandon the page before seeing the message from the ad. That is why we don't treat speed as a later optimisation but build it in from day one — through the choice of technology, design that doesn't demand needlessly heavy elements, and a disciplined way of preparing images and content for publication.