Interactive Tools
Understand Your Web Vitals Scores
Adjust sliders to see in real time how different factors affect your Core Web Vitals score.
1.70s
Largest Contentful Paint
Good
Time to First Byte (TTFB)400ms
Server response time. Target < 600ms.
Resource Load Time800ms
Time to transfer the LCP image from server to browser.
Render Delay300ms
JS/CSS blocking paint to start. Minimise render-blocking resources.
Element Render Time200ms
Browser processing time to paint the element.
LCP Breakdown: TTFB 400ms + Render Delay 300ms + Resource Load 800ms + Element Render 200ms = 1700ms
About LCP Simulator
Understand what contributes to your Largest Contentful Paint score.
Score Thresholds
Good
≤ 2.5sNeeds Work
2.5–4.0sPoor
> 4.0s💡 Tip: Google requires Good ratings on all three metrics for your page to pass Core Web Vitals assessment in Search Console.