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Pavlo K
Pavlo K

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What is PageSpeed Insights and why its scores are just an illusion of speed?

PageSpeed Insights is a popular tool from Google that helps evaluate website speed. But here’s the thing: its score is NOT the actual loading speed, but a mix of synthetic and real-world metrics that need to be interpreted correctly.

How does PageSpeed Insights work?

  • Lab Data - a test under controlled conditions using Lighthouse. It identifies potential issues but does not reflect real user experience.
  • Real-User Experience Data - statistics from the Chrome UX Report collected over the past 28 days. It shows how fast the site performs for real users across different networks and devices.
  • Field Data - real performance metrics that impact Core Web Vitals. However, if a site has low traffic, these may not be available.

Why is the PageSpeed Insights score not always objective?

  • ⚠️ Lab tests are conducted under strict conditions (slow internet, low-end hardware).
  • ⚠️ Real-user data is aggregated over a 28-day period, so recent changes won’t be reflected immediately.
  • ⚠️ The score is just a reference. Google ranks websites based on Core Web Vitals, not the "perfect" 100 PSI score.

PageSpeed Insights is a useful tool, but not the ultimate one. To get a true picture of your site’s speed, rely on Core Web Vitals in Google Search Console and Chrome UX Report instead.

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