You Are Testing on the Wrong Device
Come closer. Listen.
When you check your site speed, you open Chrome on your laptop. Fast WiFi. Fast processor. Everything loads instantly.
Your customer is on a three-year-old Samsung phone. On a congested 4G connection. In a subway.
That is the experience Google is measuring. Not yours.
The Reality Gap
A page that loads in 1.5 seconds on your MacBook might take 7 seconds on a mid-range Android phone. JavaScript execution is dramatically slower on budget devices. Network latency adds seconds.
Google's Core Web Vitals are measured from real user data. The Chrome User Experience Report captures metrics from actual visitors with actual devices on actual connections.
Mobile-Specific Speed Fixes
Reduce JavaScript. Mobile CPUs are 3-5x slower than desktop. Less JavaScript means faster execution.
Compress images aggressively. Mobile screens are smaller. You do not need 2000px-wide images for a 375px viewport. Our image optimization guide covers this in detail.
Prioritize above-the-fold content. Use `fetchpriority="high"` on your LCP image. Defer everything else.
Eliminate render-blocking resources. Inline critical CSS. Defer non-critical JavaScript.
Test on throttled connections. Chrome DevTools has network throttling. Use "Slow 4G" preset. That is closer to what real users experience.
The Test That Matters
Run PageSpeed Insights on your most important pages. Look at the mobile score, not desktop. Look at field data (real users), not lab data (simulated).
Then act on it. Track your mobile speed improvements with seocheckup.app. 113 tasks. Free. No credit card. 30 seconds.