Core Web Vitals tuned for rankings and conversions.
LCP, INP and CLS are the three metrics Google uses for Page Experience. Most sites pass on desktop and quietly fail on mobile, which is where most of the traffic actually is. I optimise both, in priority order, with real-user data not just lab tests.
target per page
on 75th percentile
for responsiveness
account layer.
Four levers that move the metrics.
Core Web Vitals are not one metric, they are three independent ones. Each has its own causes and its own fixes.
Largest Contentful Paint is usually the hero image or the H1 block. Fixes: preload the LCP element, serve in next-gen format, optimise image dimensions, reduce render-blocking CSS, move critical CSS inline.
Interaction to Next Paint measures real interactivity. Heavy JavaScript on click, third-party widgets, big input handlers are the usual culprits. I profile with Chrome DevTools and code-split the worst offenders.
Cumulative Layout Shift is mostly caused by images without dimensions, web fonts swapping in, and ad slots loading. Each has a known fix that is mostly discipline, not engineering.
PSI lab tests are a starting point. The real metric is field data from your actual visitors. I set up Web Vitals reporting in GA4 so you see how real users experience the site, not just synthetic tests.
From audit to passing on the 75th percentile.
Core Web Vitals work is best done in tight cycles. Measure, fix, re-measure. The process keeps the work scoped and the wins visible.
PSI runs on top 10-20 templates. Chrome User Experience Report (CrUX) data for real-user baseline. Lighthouse CI run on staging. Identify the worst-performing templates and the root cause per metric.
Every issue gets scored. Image weight is usually highest ROI. Web fonts second. Third-party scripts third. Render-blocking CSS fourth. The list is plugged into the dev team queue in priority order.
Implementations land in sprints. Re-measure after each. Web Vitals reporting wired into GA4 for live field data. Looker Studio dashboard shows lab vs field scores trending in the right direction.
Mobile-first, real-user, ranking-tied.
Most agencies stop at the PSI lab score. That misses two-thirds of the story. Field data shows what your real visitors experience, mobile data shows where most traffic actually is, and ranking deltas show whether Page Experience is moving rankings at all. Optimising on all three is what makes Core Web Vitals work pay off.
PSI is a lab test. CrUX and GA4 Web Vitals show what real visitors get.
Mobile is where the traffic lives. Desktop optimisation is a side-effect.
Some sites do not need full CWV work. I tell you when the budget is better spent elsewhere.
WordPress, Shopify, headless. The bottleneck pattern changes per stack, the fixes are tailored.
Site passing on desktop, failing on mobile?
Book a free 30-minute consultation. I review your PSI scores and CrUX field data beforehand and come with two or three concrete fixes worth their dev time. Even if we do not end up working together, you leave with something actionable.
PSI + CrUX review before we talk.
Concrete vervolgstappen om te behouden.