Core Web Vitals & measurement
Interpret reports and trace loading, responsiveness and layout stability.
Trusted resources
Use these primary references alongside the practical guides below.
A hero-image LCP investigation you can hand to a developer
Collect the request and render evidence needed to diagnose a slow WordPress hero instead of repeatedly compressing its image.
Read the guideConsent banners and layout shifts: diagnose the insertion pattern
Check delayed consent banners, reserved space and mobile wrapping while preserving readable choices and visitor control.
Read the guideNo Core Web Vitals field data? Interpret the gap before changing the site
Understand missing page and origin data, keep lab evidence useful, and avoid inventing conclusions from an unavailable CrUX report.
Read the guidePageSpeed Insights: why field data and lab scores disagree
Understand the report's real-user and simulated sections, missing field data and how to verify a recent performance change.
Read the guideSet WordPress performance budgets by template and visitor task
Create useful budgets for articles, landing pages and products with repeatable measurements and explicit tradeoff decisions.
Read the guideThe first click does nothing: investigate startup JavaScript contention
Trace an unresponsive first tap during WordPress startup and distinguish missing handlers from a blocked main thread.
Read the guideWhen text is the LCP element: investigate typography and rendering
Diagnose a late hero heading by tracing fonts, blocking styles and animation instead of optimizing an unrelated hero image.
Read the guideCore Web Vitals for WordPress: LCP, INP and CLS explained
Understand loading, responsiveness and stability before chasing a performance score.
Read the guideSlow WordPress interactions: a practical guide to INP
A fast-loading page still needs menus, search and filters that respond promptly.
Read the guideStop content jumping: a WordPress layout stability checklist
Reserve space for images, embeds and late-arriving content.
Read the guideWhy a smaller hero image may not improve your LCP
Look beyond file size to find what delays the largest element on your page.
Read the guide