Core Web Vitals | CSS-Tricks

Core Web Vitals is what Google is calling a a new collection of three web performance metrics:

1. LCP: Largest Contentful Paint
2. FID: First Input Delay
3. CLS: Cumulative Layout Shift

These are all measurable. They aren’t in Lighthouse (e.g. the Audits tab in Chrome DevTools) just yet, but sounds like that’s coming up soon. For now, an open source library will get you the numbers. There is also a browser extension (that feels pretty alpha as you have to install it manually).

That’s all good to me. I like seeing web performance metrics evolve into more meaningful numbers. I’ve spent a lot of time in my days just doing stuff like reducing requests and shrinking assets, which is useful, but kind of a side attack to web performance. These metrics are what really matter because they are what users actually see and experience.

The bigger news came today though in that they are straight up telling us: Core Web Vitals matter for your SEO:

Today, we’re building on this work and providing an early look at an upcoming Search ranking change that incorporates these page experience metrics. We will introduce a new signal that combines Core Web Vitals with our existing signals for page experience to provide a holistic picture of the quality of a user’s experience on a web page.

Straight up, these numbers matter for SEO (or they will soon).

And they didn’t bury the other lede either:

As part of this update, we’ll also incorporate the page experience metrics into our ranking criteria for the Top Stories feature in Search on mobile, and remove the AMP requirement from Top Stories eligibility.

AMP won’t be required for SERP carousel thing, which was the #1 driver of AMP adoption. I can’t wait to see my first non-AMP page up there! I know some features will be unavailable, like the ability to swipe between stories (because that relies on things like the Google AMP cache), but whatever, bring it on. Let AMP just be a thing people use because they want to not because they have to.