SEO Pulse Feature
Core Web Vitals
on every page you visit
LCP, FCP, CLS, TTFB, and INP displayed in one panel. One-click links to PageSpeed Insights and CrUX Vis for real-user field data — broken down by URL.
The five metrics
What SEO Pulse shows
All five performance signals displayed in the Page Info tab alongside your on-page audit data.
LCP
Largest Contentful Paint
How long it takes for the largest visible element to load. The primary loading performance signal Google uses for ranking.
≤2.5s
≤4s
>4s
FCP
First Contentful Paint
When the first text or image element appears on screen. Shows how quickly the page starts rendering something visible.
≤1.8s
≤3s
>3s
CLS
Cumulative Layout Shift
Measures visual stability — how much page elements unexpectedly shift as content loads. Images without dimensions are a common cause.
≤0.1
≤0.25
>0.25
TTFB
Time to First Byte
How long until the browser receives the first byte of the response. Reflects server response time and network conditions.
≤800ms
≤1.8s
>1.8s
INP
Interaction to Next Paint
Measures responsiveness — how quickly the page responds to user interactions. Replaced FID as the Core Web Vitals interactivity metric in March 2024.
≤200ms
≤500ms
>500ms
Lab data vs field data
Two data sources,
one click each
SEO Pulse links to both tools directly from the Core Web Vitals panel — no URL copying, no tab hunting.
PageSpeed Insights — Lab data
Simulated performance metrics measured in a controlled environment. Useful for identifying specific performance issues and testing the impact of changes. Not what Google uses for ranking — but essential for debugging.
Open PageSpeed Insights ↗
CrUX Vis — Real-user field data
Chrome User Experience Report data from real users visiting your page. Broken down by URL (page-level), not just origin. This is the data Google uses as a ranking signal. CrUX Vis shows p75 values — the 75th percentile of real user experiences.
Open CrUX Vis ↗
Note: CrUX field data is only available for pages with sufficient real-user traffic. Low-traffic or new pages may show "no data available" — in that case, PageSpeed Insights lab data is the best available proxy.
Related checks
CWV issues in the Issues Tab
Some Core Web Vitals issues are detectable from the DOM and surfaced directly in the Issues Tab.
Images missing width/height
Images without explicit width and height attributes cause layout shifts as they load — directly contributing to CLS. SEO Pulse flags these in the Issues Tab as a warning.
CLS impact
Render-blocking scripts
Scripts in <head> without defer or async block HTML parsing and delay FCP and LCP. SEO Pulse detects these via the Scripts & Tracking panel and flags them in the Issues Tab.
FCP / LCP impact
Images not lazy loaded
Below-the-fold images that load immediately compete with above-the-fold content for bandwidth, potentially delaying LCP. SEO Pulse flags images missing loading="lazy".
LCP impact
FAQ
Common questions
What are Core Web Vitals? +
Core Web Vitals are a set of real-world performance metrics that Google uses as ranking signals. They measure loading (LCP — Largest Contentful Paint), interactivity (INP — Interaction to Next Paint), and visual stability (CLS — Cumulative Layout Shift). Google officially incorporated Core Web Vitals into its ranking algorithm in 2021 and updated the interactivity metric from FID to INP in March 2024.
What is the difference between lab data and field data? +
Lab data is measured in a controlled environment using simulated conditions — like PageSpeed Insights. It's useful for debugging and testing changes. Field data comes from real Chrome users visiting your actual pages and is collected in the Chrome User Experience Report (CrUX). Google uses field data for ranking. Lab data can be a useful proxy when field data isn't available for low-traffic pages.
Does SEO Pulse measure Core Web Vitals directly? +
SEO Pulse displays Core Web Vitals data in the Page Info tab and provides direct links to PageSpeed Insights and CrUX Vis for both lab and field data. It also detects DOM-level issues that can affect CWV scores — such as images missing dimensions (CLS), images not lazy loaded (LCP), and render-blocking scripts (FCP/LCP) — and surfaces these in the Issues Tab.
What is CrUX Vis? +
CrUX Vis is a free visualisation tool from Google that shows Chrome User Experience Report (CrUX) data broken down by URL. Unlike PageSpeed Insights which shows origin-level field data by default, CrUX Vis shows page-level field data — so you can see real-user performance metrics for a specific URL rather than the whole domain. SEO Pulse links directly to CrUX Vis pre-populated with the current page URL.
What is INP and why did it replace FID? +
INP (Interaction to Next Paint) measures how quickly a page responds to all user interactions throughout the entire visit — clicks, taps, keyboard inputs. FID (First Input Delay) only measured the delay before the browser could begin processing the first interaction. INP is a more comprehensive measure of responsiveness across the full page lifecycle. Google replaced FID with INP as the Core Web Vitals interactivity metric in March 2024.
Check Core Web Vitals on any page
Install SEO Pulse, open a page, find CWV data in the Page Info tab.
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