Core Web Vitals in 2025
Google’s Core Web Vitals are a set of real-world performance metrics that directly influence search rankings. They measure three things: Largest Contentful Paint (LCP) — how fast the main content loads; Interaction to Next Paint (INP) — how responsive the page feels when users interact; and Cumulative Layout Shift (CLS) — how stable the layout is as the page loads.
Most UK business websites fail at least one of these thresholds. Slow load times, bloated WordPress themes, unoptimised images, and render-blocking scripts are the primary culprits. The business cost is twofold: lower rankings and higher bounce rates. A one-second delay in page load time is associated with a 7% reduction in conversions — a statistic that rarely makes it into web design briefs.
SEO-ready site architecture
Good site architecture isn’t something you bolt on after a site is built — it has to be planned from the wireframe stage. URL structures, internal linking, heading hierarchy, canonical tags, and XML sitemaps all need to be intentional from day one. Retrofitting these elements onto a poorly-structured site is expensive and often incomplete.
“Every website we build starts with an SEO audit of the client’s existing site and a competitor analysis. We design the architecture around the keywords they need to rank for before we write a single line of code.”
— Marcus Taylor, Head of Web Development, Synap GrowthKey architectural decisions that affect SEO include how service or product pages are structured, whether category pages are crawlable and indexable, how pagination is handled, and whether the site uses server-side rendering or client-side JavaScript frameworks that can cause crawling issues.
Conversion-focused design principles
A website that ranks but doesn’t convert is just an expensive brochure. Conversion rate optimisation (CRO) isn’t a separate discipline from web design — it should be embedded in every layout decision.
- Single, clear CTA per section — Visitors shouldn’t have to decide between five different actions. Guide them to one next step.
- Social proof above the fold — Testimonials, client logos, and trust signals reduce anxiety before a visitor has read a word of your copy.
- Benefit-led headlines — What does the visitor get? Lead with the outcome, not the process.
- Friction reduction — Every additional form field, page load, or decision point reduces conversion probability. Remove anything that isn’t necessary.
- Mobile CTA visibility — On mobile, CTAs need to be immediately visible without scrolling. Sticky headers with contact options dramatically improve mobile conversion rates.
Run a 5-second test on your homepage. Show it to someone unfamiliar with your business for exactly five seconds, then ask them: what does this company do, and what should I do next? If they can’t answer both questions, your hero section needs work.
Schema markup and structured data
Schema markup is code added to your website that helps Google understand the content and context of your pages. It’s the mechanism that powers rich results — star ratings, FAQ dropdowns, event dates, and product prices appearing directly in search results. These rich results typically achieve significantly higher click-through rates than standard listings.
For service businesses, the most impactful schema types are LocalBusiness, Service, FAQPage, Review, and BreadcrumbList. For e-commerce, Product schema with price, availability, and review data is essential. Despite how impactful this is, the majority of UK business websites have either no schema or incorrectly implemented schema.
Mobile-first is non-negotiable
Google indexes the mobile version of your website first. This has been the case since 2019, yet a significant proportion of UK business websites were clearly designed for desktop and adapted for mobile as an afterthought. The result is poor mobile experiences that rank poorly and convert poorly.
True mobile-first design means designing the mobile experience first, then expanding it for larger screens — not the reverse. It means touch-friendly tap targets, thumb-accessible navigation, and content hierarchy that works in a single column. It means testing performance on mid-range Android devices, not just a MacBook Pro on a fast Wi-Fi connection.