What are Core Web Vitals?
Core Web Vitals are three Google measures of how a page feels to real visitors: LCP for loading, INP for how fast it answers a tap, and CLS for how much the layout jumps. A page passes when each is Good on at least 3 in 4 visits: loading within 2.5 seconds, reacting within 200 milliseconds, shifting 0.1 or less.
LCP, INP and CLS: what counts as good?
| Measure | What it measures | Good | Poor |
|---|---|---|---|
| LCP, Largest Contentful Paint | How long the biggest photo or block of text takes to show | 2.5 seconds or less | Over 4 seconds |
| INP, Interaction to Next Paint | How long the page takes to answer a tap, click or key press | 200 milliseconds or less | Over 500 milliseconds |
| CLS, Cumulative Layout Shift | How much things on the page jump without warning, as a score | 0.1 or less | Over 0.25 |
Google calls the band in between "needs improvement". Phones and computers are graded apart. In March 2024, INP replaced First Input Delay.
Do Core Web Vitals affect your Google ranking?
Yes, Google's ranking systems use them, but relevance comes first. A better experience can help when many pages answer a search equally well. Chasing a perfect score for SEO alone, in Google's words, "may not be the best use of your time."
Where do you see Core Web Vitals in Shopify?
At the top of the Online Store page in your admin, Shopify's performance summary rates "LCP P75" and "INP P75" as Good, Moderate or Poor from 30 days of real visits. P75 means 3 in 4 visits were that fast or faster. Moderate is Shopify's word for "needs improvement". Google's Search Console reads Chrome's own visit data, so its figures can differ.
Say your LCP tile reads 3100 milliseconds, or 3.1 seconds. That's Moderate: 0.6 seconds slower than Good and 0.9 seconds short of Poor.
How do you improve Core Web Vitals on Shopify?
Start with the three things Shopify's help says weigh most: your theme, your apps and tracking tags added by hand. For LCP, check each page's first big photo, and show fewer large ones on a slow page. On 73% of mobile pages, the biggest thing on screen is an image, per the HTTP Archive's 2024 Web Almanac. INP suffers when apps and tags keep the page busy as a shopper taps, so remove the ones you don't use. CLS climbs when a banner, pop-up or app widget loads late and pushes the page down. How to improve Shopify store speed lists the fixes you can click, and whether apps slow your store helps you find the heavy one.
See where visits end, with Sledge
Sledge does not measure or fix your Core Web Vitals. Under "Where customers leave", Sledge Analytics shows how many visits end on each kind of page, such as product, collection or search pages, so you know which to check first. Analytics runs on the 14-day trial too. Growth Intelligence turns on when you pick a paid plan. It totals the sales its suggested fixes could add as one figure in your store's currency, labeled "Est. potential".
