75th percentile (p75)

Field performance is not summarized by averages. Core Web Vitals are assessed at the 75th percentile of real page loads, separated by device form factor: the reported value is one that 75% of visits achieved or bettered.

p75 was chosen as strict enough to represent most users while tolerant of extreme outliers — one catastrophic load on hotel Wi-Fi does not define the page. Higher percentiles like p95 and p99 remain useful diagnostics for tail latency, which is where systemic problems hide.