Free PageSpeed & Core Web Vitals Checker
Check your PageSpeed score
and Core Web Vitals — free
LCP, CLS, INP, FCP, TTFB, TBT — mobile and desktop. Powered by Google Lighthouse. No signup required.
What are Core Web Vitals?
LCPGood: < 2.5s
Largest Contentful Paint
How long until the largest visible element loads. Direct ranking signal in Google Search.
CLSGood: < 0.1
Cumulative Layout Shift
How much the page shifts visually during load. Affects user experience and rankings.
INPGood: < 200ms
Interaction to Next Paint
How fast the page responds to user interactions. Replaced FID as a Core Web Vital.
FCPGood: < 1.8s
First Contentful Paint
When the first content appears on screen. Affects perceived load speed.
TTFBGood: < 800ms
Time to First Byte
How fast your server responds. Slow TTFB hurts everything downstream.
TBTGood: < 200ms
Total Blocking Time
How long the main thread is blocked. Correlates with INP and interactivity.
Track PageSpeed trends over time
One-time tests don't tell the full story. SiteBrief monitors Core Web Vitals daily and alerts you when performance drops.
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