PageSpeed Insights
Google's official performance diagnostic, combining field data sampled from real Chrome users with lab data generated by a simulated audit.
Analogy Mental model
A road test with actual owners plus a rolling-road test in the workshop. One tells you how the car behaves in daily traffic, the other tells you its limits under controlled conditions.
In practice What you actually do
Test the homepage, a core category page, and a representative detail page. Start with the field data section at the top and confirm the three Core Web Vitals pass there. Then screenshot the specific red diagnostics and put them in a ticket, because a developer needs the item named, not a score.
Where people get burned Pitfalls
Chasing a perfect lab score by stripping out chat widgets and analytics is a net loss. If the field data shows all three vitals passing, a lab score of seventy-five and a lab score of ninety-eight rank identically.
This entry was written in English from the Chinese original, not machine-translated. Read the Chinese version →