Free Grader

Core Web Vitals
Grade Your Site

Get a detailed A–F grade for LCP, CLS, INP, FCP, TBT and TTFB — with a prioritised fix plan tailored to your scores.

LCP
Largest Contentful Paint
LCP
Good =2.5sOK =4sPoor >4s
s
CLS
Cumulative Layout Shift
CLS
Good =0.1OK =0.25Poor >0.25
score
INP
Interaction to Next Paint
INP
Good =200msOK =500msPoor >500ms
ms
FCP
First Contentful Paint
FCP
Good =1.8sOK =3sPoor >3s
s
TBT
Total Blocking Time
TBT
Good =200msOK =600msPoor >600ms
ms
TTFB
Time to First Byte
TTFB
Good =800msOK =1800msPoor >1800ms
ms
Grading your Core Web Vitals...
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Frequently Asked Questions

Core Web Vitals are Google's official metrics for measuring real-world user experience on a webpage. They cover three areas: loading (LCP — Largest Contentful Paint), interactivity (INP — Interaction to Next Paint), and visual stability (CLS — Cumulative Layout Shift). Google uses them as a ranking signal in search results.

A good LCP (Largest Contentful Paint) score is 2.5 seconds or faster. Scores between 2.5s and 4s need improvement, and anything above 4 seconds is considered poor and will hurt your search rankings. LCP measures when the largest visible element in the viewport finishes rendering.

Check your Core Web Vitals at least once a week for active sites, and after every major change (new theme, new plugin, large content additions, or any code deploy). Google Search Console tracks CWV continuously using real-user data — review that report at least monthly to catch regressions early.

Yes. Since June 2021, Core Web Vitals are part of Google's page experience ranking signal. While CWV alone won't make or break your rankings, poor vitals can hold back otherwise great content from reaching its full ranking potential. Fast sites also have lower bounce rates and higher conversion rates.

FCP (First Contentful Paint) measures when the first piece of content appears on screen. LCP (Largest Contentful Paint) measures when the largest visible element finishes rendering. LCP is the better indicator of when a user perceives the page as "loaded" — for example, FCP might fire when a tiny text node paints, while LCP waits for the hero image to appear.

FID (First Input Delay) measured only the delay of the first user interaction. INP (Interaction to Next Paint) measures the responsiveness of all interactions throughout the page's lifecycle. Google replaced FID with INP as an official Core Web Vital in March 2024 because it's a far more accurate measure of real user experience.