Five metrics. Real visitors.
What Chrome users actually experienced on this page and this site over the last 28 days.
- LCP2.1 s
- INP160 ms
- CLS0.04
The three Core Web Vitals
0 ptsLargest Contentful Paint, Interaction to Next Paint and Cumulative Layout Shift at the 75th percentile, rated good, needs improvement or poor against Google's thresholds.
Supporting metrics
0 ptsFirst Contentful Paint and Time to First Byte, the two diagnostics that usually explain a slow LCP.
Distribution, not just p75
0 ptsThe share of visits that were good, needs improvement and poor for every metric, so you see how close you are to passing.
Page and origin, mobile and desktop
0 ptsUp to four records: this page and the whole site, each on phones and on desktops, since Google assesses page groups on mobile first.
- Meta tags
- Headings
- Images
- Schema
- Mobile
Pass or fail verdict
0 ptsA page passes when all three core metrics are good at p75. The verdict is shown for every record found.
Field data from Chrome
0 ptsReal visits over the last 28 days from the Chrome UX Report, the same dataset behind Search Console's Page Experience report.
Lab scores lie.
Field data ranks.
Lab tools measure one simulated load. Google ranks on what real Chrome users experienced over the last 28 days. Those two numbers disagree more often than you would think.
Field data is what Google uses
The page experience signal and the Search Console report are built from the Chrome UX Report. A green Lighthouse score with poor field data still fails.
p75 is a high bar
A metric is good only if 75% of visits are good. A page that is fast on your laptop can fail because a quarter of visitors are on slow phones.
Mobile decides
Google assesses mobile and desktop separately and uses mobile for mobile rankings, which is most of them. Fix mobile first.
Fix the failing metric. Then wait for the 28-day window.
- 1
Start with the failing core metric
The verdict names it. LCP is usually the hero image or a render-blocking font; INP is heavy JavaScript on tap; CLS is images without dimensions or late-loading banners.
- 2
Cut LCP with the basics
Preload the hero image, serve it in a modern format at the right size, inline critical CSS and put the page behind a CDN. TTFB under 800 ms makes everything else easier.
- 3
Fix INP by doing less on the main thread
Break long tasks, defer third-party scripts, and respond to taps before running heavy work. Most INP problems are tag managers and chat widgets.
- 4
Stop layout shift at the source
Give every image, ad slot and embed explicit width and height, and never inject content above what the user is reading.
- 5
Wait 28 days and re-check
The Chrome UX Report is a rolling 28-day window. Improvements show up gradually; check weekly until the p75 crosses the good threshold.
Get told before Core Web Vitals slip
SiteLift runs technical audits on a schedule, tracks Core Web Vitals and indexability, and flags regressions before they cost rankings.
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Frequently Asked Questions
Everything you need to know about the core web vitals checker.
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