Level: Intermediate
Unexpected layout shift — content jumping around as a page finishes loading — is jarring and can even cause accidental clicks on the wrong element.
Reserve Space for Images and Embeds in Advance
Defining explicit dimensions for images and embedded content before they load prevents the surrounding layout from shifting once they actually appear.
Be Careful With Dynamically Injected Content
Content inserted above existing content after the initial render, like a promotional banner, is a common and often overlooked cause of layout shift.
Test With Real Network Conditions, Not Just a Fast Connection
Layout shift issues are often more pronounced and more noticeable under slower, more realistic network conditions than they appear on a fast office connection.
Next step: Use the Pagespeed Insights Checker to check your Core Web Vitals report to identify exactly which elements are contributing to layout shift on your pages.