Core Web Vitals deep dive
Core Web Vitals are still one of the clearest ways to diagnose whether templates are delivering a poor real-user experience. This guide now absorbs the shorter CWV and mobile checklist material, so it covers both the underlying metrics and the mobile-specific realities that cause many sites to fail in production.
LCP and mobile delivery
Largest Contentful Paint is often driven by server response, image delivery, and render-blocking work. Those issues become harsher on real mobile devices and slower connections, so test with field data and realistic throttling. Improve the delivery of the main visual element, reduce early blocking resources, and avoid lazy-loading content that should appear immediately.
- Use field data and realistic mobile testing
- Prioritise the main above-the-fold asset
- Reduce render-blocking work
Interactivity, stability, and page experience
Poor interactivity and layout stability usually come from heavy JavaScript, injected content, ads, embeds, and unsized images. These issues are partly technical and partly template-driven. Fix them where they repeat across page groups, and make sure the mobile layout remains usable with clear tap targets, stable rendering, and minimal late shifts.
- Break up heavy JavaScript work
- Reserve space for unstable elements
- Keep mobile layouts usable and stable