Core Web Vitals Troubleshooting: Fixing LCP, INP and CLS

A failing Core Web Vitals score is rarely one problem. It is usually three separate issues hiding behind one number. Diagnosing each metric on its own, then applying the fix that matches the cause, is the fastest way to pass the assessment.

We deliver this through our Security & Performance service for businesses across Australia.

Start with field data, not lab data

Lab tools like Lighthouse simulate a single load. Field data from the Chrome User Experience Report shows what real visitors experience over time. Always fix for field data first, because that is what Google ranks on.

Fixing Largest Contentful Paint

LCP measures how long the main content takes to appear. It usually fails because of a slow server response, an unoptimised hero image or render-blocking resources. Address the largest element first.

Fixing Interaction to Next Paint

INP replaced First Input Delay as the responsiveness metric. It fails when heavy JavaScript blocks the main thread while a visitor taps or types. Breaking up long tasks and trimming third-party scripts is the cure.

Fixing Cumulative Layout Shift

CLS measures unexpected movement as the page loads. It fails when images, ads or embeds have no reserved space. Set width and height on every image, reserve space for embeds and avoid inserting content above existing content.

MetricCommon causePrimary fix
LCPHeavy hero imageCompress, preload, set dimensions
INPBlocking JavaScriptSplit long tasks, cut third-party scripts
CLSUnsized mediaReserve space for images and embeds

Re-test and monitor

Field data updates on a rolling basis, so a fix can take several weeks to show in Search Console. Keep lab testing for instant feedback, then confirm the win in field data before you call it done.

Fix one metric at a time and re-measure. Changing several things at once makes it impossible to know which fix worked.

Key takeaways

Frequently asked questions

How often should a business website be updated for security?

Core security updates for the CMS, plugins and server should be applied weekly or immediately when a critical patch is released. A monthly maintenance schedule is the minimum for most business sites.

Where is TPR Media based?

TPR Media operates from Level 34, 1 Eagle Street, Brisbane City QLD 4000, serving clients across Brisbane and Australia-wide.

TPR Media troubleshoots Core Web Vitals for Australian businesses, diagnosing and fixing LCP, INP and CLS with prioritised changes confirmed against field data.