Question 1

What are the mobile Core Web Vitals for web.dev?

Accepted Answer

web.dev mobile (phone form factor) p75 metrics from Google CrUX: LCP 3116ms (needs-improvement), INP 194ms (good), CLS 0.040 (good). Mobile reflects real-world conditions for the ~60% of web traffic that's mobile-first.

Question 2

Why are mobile vitals usually worse than desktop for web.dev?

Accepted Answer

Mobile devices have constrained CPU + RAM + cellular network conditions vs desktop's wired connection. Typical mobile shows 30-60% slower LCP + 40-70% higher INP than desktop on the same site. CLS varies less by device. Mobile is also Google's primary ranking signal — mobile vitals directly affect search rankings.

Question 3

How current is the mobile CrUX data for web.dev?

Accepted Answer

Collection window: 2026-07-24 to 2026-08-20. Google CrUX publishes monthly aggregates derived from 28-day p75 trailing measurements of real Chrome users on phone devices. Refresh cadence is automated.