So you're passing your site through Google's PageSpeed Insights and you notice a big red "Failed" on your Core Web Vitals segment for mobile performance. You start going into a panic, you remember that time you flunked your biology test and it all comes rushing back. Well, one of the main culprits in the case of the Core Web Vital's failure will likely be your score in regards to the CLS, or Cumulative Layout Shift.
Today, we're going to dive in to explain to you how you can fix this metric with a Blogspot/Blogger blog to improve upon your core web vitals so that you can also improve your rankings. It's important to note that this is not the only metric considered within the Core Web Vitals but, as its name suggests, it's one of the "Vital" ones according to Google.
So, what is the CLS anyhow?
Cumulative Layout Shift (CLS) is a web performance metric that measures the visual stability of a page. Specifically, it quantifies how much unexpected layout shift occurs as a page loads and while the user interacts with it. Unexpected layout shifts can be jarring for users, making it difficult for them to interact with a page, so a lower CLS score indicates a more stable page from a user's perspective.
Here's how CLS works:
Layout Shift Score: Every time an element on the page changes its visual position, a layout shift score is calculated for that individual shift. The score is a product of two factors:
Impact Fraction: The percentage of the viewport that was displaced during the shift.
Distance Fraction: The distance the unstable element has moved, relative to the viewport's largest dimension (usually the height on mobile devices and width on desktop).
Cumulative Score: Over the lifecycle of the page, each individual layout shift score is added together to get the "cumulative" layout shift score. This total is the CLS.











